Playwright MCP

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description adds minimal behavioral context beyond annotations. Annotations already indicate destructiveHint=true (modifies page state) and readOnlyHint=false (not read-only), which aligns with 'perform click' implying interaction. However, the description doesn't elaborate on what 'perform click' entails (e.g., triggering events, navigation) or mention potential side effects like page changes, which would be valuable given the destructive nature. No contradiction with annotations exists.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is extremely concise with a single sentence ('Perform click on a web page'), which is front-loaded and wastes no words. Every part of the sentence directly contributes to understanding the tool's purpose without redundancy or unnecessary elaboration.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (destructive interaction with 5 parameters) and lack of output schema, the description is minimally adequate. Annotations cover safety aspects (destructive, not read-only), but the description doesn't address return values or error conditions. For a tool that modifies page state, more context on outcomes would be beneficial, though annotations provide some baseline.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so parameters are fully documented in the schema. The description adds no additional meaning about parameters beyond the schema's details (e.g., element and ref requirements, button options). It doesn't explain why both element and ref are needed or how they interact, leaving the schema to carry the full burden.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('perform click') and resource ('on a web page'), making the purpose immediately understandable. It distinguishes itself from siblings like browser_hover, browser_press_key, and browser_drag by specifying clicking rather than hovering, typing, or dragging. However, it doesn't explicitly differentiate from all siblings (e.g., browser_select_option might also involve clicking).

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention when to choose click over other interaction methods like browser_type or browser_press_key, nor does it specify prerequisites (e.g., needing a page snapshot first). The context is implied but not explicitly stated.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate destructiveHint=true and readOnlyHint=false, which the description aligns with by implying a destructive close operation. The description adds value by specifying 'the page' as the target, clarifying scope beyond what annotations provide. However, it doesn't mention potential side effects like data loss or confirmation dialogs, which would enhance transparency for a destructive tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, clear sentence with zero wasted words. It's front-loaded with the core action ('Close') and immediately specifies the target ('the page'), making it highly efficient. Every word earns its place in conveying the tool's function.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's destructive nature (per annotations) and lack of output schema, the description is minimally adequate. It covers the basic action but doesn't address implications like what happens after closing (e.g., browser state, return values) or error conditions. For a destructive tool with no output schema, more context would improve completeness.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0 parameters and 100% schema description coverage, the baseline is 4. The description doesn't need to explain parameters, and it efficiently states the action without redundancy. No additional parameter context is required or provided, which is appropriate for a parameterless tool.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Close the page' clearly states the action (close) and target (the page), making the purpose immediately understandable. It distinguishes from siblings like browser_navigate or browser_tabs by focusing on termination rather than navigation or tab management. However, it doesn't specify if it closes the current tab or entire browser, which prevents a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. The description doesn't mention prerequisites (e.g., requires an open page), exclusions (e.g., don't use if unsaved changes exist), or sibling tools that might be relevant (like browser_tabs for tab management). This leaves the agent with minimal context for decision-making.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide readOnlyHint=true, destructiveHint=false, and openWorldHint=true, indicating a safe, read-only operation with potential for varied data. The description adds minimal behavioral context beyond this—it specifies 'all console messages' but doesn't detail format, pagination, or real-time vs. cached retrieval. Since annotations cover safety, the description earns a baseline score for not contradicting them, though it could offer more operational insight.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description 'Returns all console messages' is a single, front-loaded sentence with zero waste—it directly states the core function without fluff. It's appropriately sized for a simple tool, making it easy for an agent to parse quickly and efficiently.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's low complexity (1 optional parameter), high schema coverage (100%), and annotations covering safety, the description is minimally adequate. However, without an output schema, it doesn't explain return values (e.g., message format, timestamps), leaving a gap. For a read-only tool with good annotations, it's passable but could be more informative about results.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the 'level' parameter fully documented in the schema (enum, default, description). The description adds no parameter-specific information beyond implying retrieval of messages, which the schema already covers. This meets the baseline of 3, as the schema handles parameter semantics adequately without extra description input.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Returns all console messages' clearly states the verb ('Returns') and resource ('console messages'), making the purpose understandable. However, it doesn't explicitly differentiate from sibling tools like browser_network_requests or browser_run_code, which also retrieve browser data but different types. The title annotation 'Get console messages' reinforces this, but the description itself lacks sibling distinction.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing an active browser session), exclusions, or comparisons to siblings like browser_network_requests for network logs. Without such context, an agent might struggle to choose appropriately among the many browser-related tools.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already indicate this is a destructive (destructiveHint: true), non-read-only (readOnlyHint: false) operation with open-world implications (openWorldHint: true). The description adds minimal behavioral context beyond this, as it doesn't explain what 'destructive' entails (e.g., UI state changes, data modifications) or any side effects like page reloads. No contradiction with annotations exists.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, front-loaded sentence that directly states the tool's function without unnecessary words. Every part of the sentence ('Perform drag and drop between two elements') is essential, making it highly efficient and well-structured.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (interactive, destructive action with 4 required parameters) and lack of output schema, the description is minimally adequate. It covers the basic purpose but lacks details on behavioral outcomes, error conditions, or integration with sibling tools like browser_snapshot for obtaining element references, leaving gaps in context.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with clear documentation for all four parameters (startElement, startRef, endElement, endRef). The description adds no additional meaning about parameters beyond implying they specify source and target elements, so it meets the baseline of 3 without compensating for gaps.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Perform drag and drop') and the target ('between two elements'), which is specific and unambiguous. However, it doesn't explicitly differentiate from sibling tools like browser_click or browser_hover, which are also interaction tools but for different actions.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., needing a page snapshot from browser_snapshot), nor does it clarify use cases like reordering items versus moving files, leaving the agent to infer context from sibling tool names alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide readOnlyHint=false, openWorldHint=true, and destructiveHint=true, indicating this is a mutable, potentially destructive operation with open-world assumptions. The description adds minimal behavioral context beyond this—it mentions evaluating JavaScript but doesn't clarify what 'destructive' entails (e.g., modifying page state, triggering side effects) or any rate limits, permissions, or error handling. No contradiction with annotations exists.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is extremely concise—a single, front-loaded sentence that directly states the tool's purpose without unnecessary words. Every part of the sentence ('Evaluate JavaScript expression on page or element') contributes essential information, making it efficient and well-structured.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (JavaScript evaluation with potential side effects), destructive annotations, and lack of output schema, the description is insufficient. It doesn't explain return values, error conditions, security implications, or how it differs from siblings like browser_run_code. For a tool with open-world and destructive hints, more context is needed to guide safe and effective use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with clear parameter descriptions in the schema (e.g., function as JavaScript code, element as human-readable description, ref as exact target reference). The description adds no additional parameter semantics beyond what's in the schema, such as examples of valid expressions or interaction between parameters. Baseline 3 is appropriate given high schema coverage.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('Evaluate') and resource ('JavaScript expression on page or element'), making the purpose understandable. It distinguishes from some siblings like browser_click or browser_navigate by focusing on JavaScript execution, though it doesn't explicitly differentiate from browser_run_code which might have overlapping functionality.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives like browser_run_code or other JavaScript-related tools. It mentions 'page or element' context but doesn't specify prerequisites, constraints, or typical use cases, leaving the agent to infer usage scenarios.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate destructiveHint=true and openWorldHint=true, which the description doesn't contradict. It adds that uploading can involve 'one or multiple files' and implies a file chooser fallback if paths omitted, providing some behavioral context beyond annotations. However, it lacks details on permissions, rate limits, or specific effects of the destructive operation.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence with no wasted words. It's front-loaded with the core action and resource, making it highly concise and well-structured for quick understanding.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (destructive operation with open-world hint), no output schema, and rich annotations, the description is adequate but incomplete. It covers the basic purpose but lacks context on when to use, error handling, or output expectations, leaving gaps for an agent to infer.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the parameter 'paths' fully documented in the schema. The description adds minimal semantics by implying the tool handles multiple files, but this is already covered in the schema's description. Baseline 3 is appropriate as the schema carries the burden.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Upload one or multiple files' clearly states the action (upload) and resource (files), and distinguishes from sibling tools like browser_click or browser_navigate. However, it doesn't specify the upload destination or context (e.g., to a browser session), which would make it more specific.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance on when to use this tool versus alternatives is provided. It doesn't mention prerequisites (e.g., needing an active browser session), nor does it differentiate from potential non-browser upload tools. The description alone offers no usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate this is a destructive, non-read-only operation with open-world hints, which the description aligns with by implying mutation ('fill'). The description adds value by specifying 'multiple form fields,' suggesting batch capability, though it lacks details on error handling, side effects, or dependencies. No contradiction with annotations exists.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is extremely concise with a single phrase, 'Fill multiple form fields,' which is front-loaded and wastes no words. It efficiently conveys the core action, though this brevity contributes to gaps in other dimensions.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the complexity of a destructive tool with no output schema and rich annotations, the description is incomplete. It doesn't explain return values, error conditions, or how it integrates with sibling tools (e.g., browser_snapshot for 'ref' values). For a tool that modifies browser state, more context is needed to guide safe and effective use.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema fully documents the 'fields' parameter and its nested properties. The description adds no additional meaning beyond implying batch processing ('multiple'), which is already clear from the array type in the schema. Baseline 3 is appropriate as the schema handles parameter documentation.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Fill multiple form fields' states the action (fill) and resource (form fields), but is vague about scope and differentiation. It doesn't specify whether this is for web forms, desktop applications, or other contexts, nor how it differs from sibling tools like browser_type or browser_select_option that also interact with form elements.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. The description doesn't mention prerequisites (e.g., needing a browser session or page snapshot), nor does it compare to similar tools like browser_type (for text input) or browser_select_option (for dropdowns), leaving the agent to guess based on context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide critical behavioral hints: destructiveHint=true indicates potential data loss or irreversible changes, and openWorldHint=true suggests it operates in dynamic environments. The description adds no behavioral context beyond these annotations, such as what specifically gets destroyed or typical dialog scenarios. However, it doesn't contradict the annotations, so it meets the minimum baseline when annotations carry the burden.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is extremely concise at two words, which is efficient and front-loaded. However, it's arguably under-specified rather than optimally concise, as it lacks necessary detail for clarity. Every word earns its place, but more content would improve utility without sacrificing brevity.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (handling browser dialogs with destructive potential) and lack of output schema, the description is incomplete. It doesn't explain what 'handle' means operationally, what types of dialogs are supported, or what the expected outcomes are. Annotations help but don't fully compensate for the sparse description in this context.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with clear parameter documentation: 'accept' determines dialog acceptance, and 'promptText' is for prompt dialogs. The description adds no additional meaning about parameters, such as examples or edge cases. With high schema coverage, the baseline score of 3 is appropriate, as the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Handle a dialog' is a tautology that restates the tool name without specifying what type of dialog or what handling entails. It doesn't distinguish this from sibling tools like browser_click or browser_select_option, which also interact with browser elements. The verb 'handle' is vague compared to more specific sibling actions like 'click', 'navigate', or 'type'.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives. The description doesn't indicate what types of dialogs it handles (e.g., alert, confirm, prompt) or in what browser contexts it applies. With siblings like browser_click for general interactions, there's no differentiation to help an agent choose appropriately.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide key behavioral hints: readOnlyHint=false, openWorldHint=true, and destructiveHint=true, indicating this is a mutable, open-world operation with potential destructive effects. The description adds minimal context beyond this, as 'Hover over element on page' doesn't disclose additional traits like what 'destructive' entails (e.g., unintended page changes) or any rate limits. It doesn't contradict annotations, but offers little extra insight, meeting the lower bar with annotations present.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description 'Hover over element on page' is extremely concise and front-loaded, consisting of a single, direct sentence that immediately conveys the core action. There is no wasted language or unnecessary elaboration, making it efficient for quick understanding without sacrificing clarity.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity (interactive browser action with destructive potential), the description is minimal but adequate when combined with annotations and a well-documented schema. It lacks output schema or details on return values, but annotations cover safety and world hints. The description could be more complete by explaining hover effects or prerequisites, but it meets basic needs without being misleading.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with clear descriptions for both parameters: 'element' as a human-readable description for permission and 'ref' as an exact target reference. The description adds no parameter-specific information beyond what the schema provides, such as examples or usage notes. Given the high schema coverage, the baseline score of 3 is appropriate, as the description doesn't compensate but also doesn't detract.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Hover over element on page' clearly states the action (hover) and target (element on page), making the purpose immediately understandable. It distinguishes itself from siblings like 'browser_click' or 'browser_type' by specifying a hover interaction rather than click or typing. However, it doesn't explicitly differentiate from other mouse-related tools like 'browser_drag' beyond the verb, which keeps it from a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention scenarios where hovering is appropriate (e.g., to trigger dropdowns or tooltips) or when to avoid it (e.g., for direct interactions like clicking). With siblings like 'browser_click' and 'browser_drag' available, the lack of usage context leaves the agent to infer when this specific mouse action is needed.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate destructiveHint=true and readOnlyHint=false, which the description aligns with by implying installation (a write operation). The description adds valuable context about error handling and prerequisites, though it doesn't detail installation behavior like time or system requirements.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is two concise sentences that are front-loaded with the main purpose and followed by specific usage guidance. Every word contributes to understanding without redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a zero-parameter tool with annotations covering safety and world hints, the description is mostly complete. It explains purpose and usage well but lacks details on installation outcomes or error specifics, which could enhance completeness.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 0 parameters and 100% schema coverage, the baseline is 4. The description adds no parameter information, which is appropriate since there are no parameters to document, maintaining clarity.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Install') and resource ('browser specified in the config'), making the purpose understandable. It distinguishes from siblings by focusing on installation rather than browser interaction, though it doesn't explicitly name alternatives.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides explicit guidance on when to use this tool: 'Call this if you get an error about the browser not being installed.' This gives clear context for invocation and distinguishes it from other browser tools that require an already-installed browser.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate readOnlyHint=false, openWorldHint=true, and destructiveHint=true, covering safety and scope. The description adds minimal behavioral context beyond this, as 'Navigate to a URL' implies a navigation action but doesn't detail effects like page loading or potential side effects. It doesn't contradict annotations, so it earns a baseline score for adding some value without rich disclosure.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence ('Navigate to a URL') that is front-loaded and wastes no words. It directly conveys the core action without unnecessary elaboration, making it highly concise and well-structured for quick understanding.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity (navigation with destructive potential), annotations provide safety and scope hints, but there's no output schema. The description is minimal and doesn't explain return values or behavioral nuances like error handling. It's adequate as a basic descriptor but lacks depth for full contextual understanding, aligning with a minimum viable score.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with the 'url' parameter fully documented. The description doesn't add any semantic details beyond what the schema provides (e.g., URL format or validation). According to rules, with high schema coverage, the baseline is 3, as the description doesn't compensate but doesn't need to.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb ('Navigate') and resource ('to a URL'), making the purpose immediately understandable. It distinguishes this tool from siblings like browser_click or browser_type by focusing on URL navigation. However, it doesn't specify what 'navigate' entails in this browser context (e.g., loading a webpage), which prevents a perfect score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention when navigation is appropriate (e.g., for loading pages) or when not to use it (e.g., for interactions like clicking), nor does it reference sibling tools like browser_navigate_back for backward navigation. This leaves the agent without context for tool selection.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide readOnlyHint=false, openWorldHint=true, and destructiveHint=true, indicating this is a mutable, potentially destructive action with open-world behavior. The description adds value by specifying 'previous page,' which clarifies the scope of the action beyond what annotations convey. However, it doesn't detail side effects like history changes or potential page reloads, so it's not fully comprehensive but still adds useful context without contradicting annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description 'Go back to the previous page' is a single, efficient sentence that is front-loaded with the core action. It wastes no words and directly communicates the tool's function, making it highly concise and well-structured for quick understanding.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's low complexity (0 parameters, no output schema) and rich annotations (covering safety and behavior), the description is mostly complete. It specifies the action and target, but could benefit from mentioning potential outcomes like navigation failure or history state. However, with annotations handling key behavioral aspects, the description is adequate for the context, though not exhaustive.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 0 parameters with 100% coverage, so no parameters need documentation. The description doesn't add parameter details, which is appropriate here. A baseline of 4 is applied as per the rules for 0 parameters, since the description doesn't need to compensate for any schema gaps and aligns well with the empty schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Go back to the previous page' clearly states the action (go back) and the resource (previous page) with a specific verb. It distinguishes this tool from siblings like 'browser_navigate' (which goes to a new page) and 'browser_tabs' (which manages tabs), making the purpose unambiguous and well-differentiated.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage context (when you want to return to a previous page in browser navigation), but does not explicitly state when NOT to use it or name alternatives. For example, it doesn't specify that this should be used instead of 'browser_navigate' for backward navigation or mention prerequisites like requiring a browser session with history. The context is clear but lacks explicit exclusions or named alternatives.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already provide key behavioral hints (readOnlyHint: true, destructiveHint: false, openWorldHint: true), indicating it's a safe read operation with potentially open-ended data. The description adds context about the temporal scope ('since loading the page'), which is useful but doesn't elaborate on aspects like data format, pagination, or rate limits. With annotations covering safety, this earns a baseline score for adding some value.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, clear sentence with no wasted words, effectively front-loading the core purpose. It's appropriately sized for a tool with one optional parameter and good annotations, making it easy to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's low complexity (1 parameter, 100% schema coverage, annotations present), the description is adequate but has gaps. It lacks output details (no output schema), usage context, and doesn't fully compensate for the absence of behavioral specifics like data format. With annotations providing safety info, it's minimally viable but not comprehensive.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the parameter 'includeStatic' fully documented in the schema. The description doesn't add any parameter-specific information beyond what's in the schema, so it meets the baseline score where the schema handles the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose with a specific verb ('Returns') and resource ('all network requests since loading the page'), making it easy to understand what the tool does. However, it doesn't explicitly differentiate from sibling tools like browser_console_messages or browser_snapshot, which might also provide browser activity data, so it doesn't reach the highest score.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention any prerequisites, context for usage, or comparisons to sibling tools like browser_console_messages, leaving the agent to infer usage based on the purpose alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate destructiveHint=true and readOnlyHint=false, which the description doesn't contradict. The description adds value by specifying the action is on a keyboard, but it doesn't elaborate on behavioral traits like whether this simulates a physical key press, if it triggers browser events, or any side effects. With annotations covering safety, this is adequate but not rich in context.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, clear sentence with no wasted words, making it easy to parse and understand quickly. It's front-loaded with the core action, which is ideal for tool selection.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (simple action with one parameter) and rich annotations (destructiveHint=true, openWorldHint=true), the description is minimally adequate. However, with no output schema and siblings like 'browser_type', it could benefit from more context about differences or return values to be fully complete.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with the 'key' parameter well-documented in the schema itself. The description doesn't add any semantic details beyond what's in the schema, such as examples of key names or special cases. Baseline 3 is appropriate since the schema does the heavy lifting.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('press') and target ('key on the keyboard'), making the purpose immediately understandable. However, it doesn't differentiate from sibling tools like 'browser_type' or 'browser_click', which also involve keyboard/mouse interactions, leaving some ambiguity about when to choose this specific tool over alternatives.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives like 'browser_type' or 'browser_click'. It lacks context about typical use cases (e.g., pressing special keys like Enter or Arrow keys) or prerequisites, leaving the agent to infer usage from the tool name alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate destructiveHint=true and readOnlyHint=false, which the description aligns with by implying a mutation (resizing). The description adds context beyond annotations by specifying it affects the 'browser window' (not just a tab or element), but doesn't detail side effects (e.g., might trigger page reloads, affect viewport-dependent content). No contradiction with annotations, and it provides some useful behavioral context.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, front-loaded sentence ('Resize the browser window') that directly conveys the core function without any wasted words. It's appropriately sized for a simple tool and earns its place by clearly stating the action and target.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity (a destructive operation with two parameters), the description is minimally adequate. Annotations cover safety (destructive) and mutability, and the schema fully documents parameters. However, with no output schema, the description doesn't explain return values (e.g., success confirmation, error handling), and it lacks context about integration with sibling tools. It meets basic needs but has clear gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 100% description coverage, with clear documentation for width and height parameters. The description doesn't add any meaning beyond the schema (e.g., units, valid ranges, or default behaviors). According to the rules, with high schema coverage, the baseline is 3, which is appropriate here as the schema carries the full burden of parameter documentation.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Resize the browser window' clearly states the action (resize) and resource (browser window), making the purpose immediately understandable. It distinguishes from siblings like browser_close or browser_navigate by specifying the resize operation. However, it doesn't explicitly differentiate from all siblings (e.g., browser_snapshot might also involve window dimensions), so it falls short of a perfect 5.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It doesn't mention prerequisites (e.g., requires an active browser session), exclusions (e.g., not for mobile browsers), or context (e.g., use before taking screenshots for consistent sizing). With siblings like browser_take_screenshot that might benefit from resizing, this lack of guidance is a significant gap.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate readOnlyHint=false, openWorldHint=true, and destructiveHint=true, covering safety and scope. The description adds value by specifying that the code runs Playwright snippets, implying browser automation with potential side effects, which aligns with annotations. However, it doesn't detail execution limits, error handling, or resource implications beyond the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient phrase 'Run Playwright code snippet' that is front-loaded and wastes no words. It directly conveys the core purpose without unnecessary elaboration, making it highly concise and well-structured.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (executing arbitrary code with destructive potential), annotations provide safety hints, and the schema fully describes the parameter. However, with no output schema and minimal description, it lacks details on return values, error cases, or execution context, leaving gaps for an agent to handle this powerful tool effectively.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with the schema fully documenting the 'code' parameter as a JavaScript function for Playwright execution. The description adds no additional parameter semantics beyond what the schema provides, so it meets the baseline for high coverage without extra value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Run Playwright code snippet' clearly states the action (run) and resource (Playwright code snippet), distinguishing it from siblings like browser_click or browser_navigate that perform specific actions. However, it doesn't explicitly differentiate from browser_evaluate, which might also execute code, making it slightly less specific.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided on when to use this tool versus alternatives like browser_evaluate or other specific interaction tools. The description lacks context about use cases, prerequisites, or exclusions, leaving the agent to infer usage based on tool names alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide key behavioral hints: readOnlyHint=false (implies mutation), openWorldHint=true (suggests dynamic interaction), and destructiveHint=true (indicates potential changes). The description adds minimal context by specifying 'dropdown' as the target, but does not elaborate on behavioral traits like permission requirements, error handling, or the impact of selection (e.g., triggering page changes). No contradiction with annotations exists.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, direct sentence with zero wasted words, making it highly concise and front-loaded. It immediately communicates the core function without unnecessary elaboration, which is efficient for an AI agent parsing tool definitions.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (interactive, destructive action with 3 required parameters) and lack of output schema, the description is minimally complete. It identifies the target (dropdown) but omits details like return values, error conditions, or dependencies on other tools (e.g., browser_snapshot for 'ref'). Annotations help, but more context would improve usability for the agent.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with clear descriptions for all parameters (element, ref, values). The description adds no additional semantic meaning beyond the schema, such as explaining how 'values' correspond to dropdown options or the interaction between 'element' and 'ref'. The baseline score of 3 reflects adequate schema documentation without extra value from the description.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description 'Select an option in a dropdown' clearly states the action (select) and target resource (dropdown), making the purpose immediately understandable. However, it does not explicitly differentiate from sibling tools like browser_fill_form or browser_click, which might also interact with form elements, leaving room for ambiguity in distinguishing use cases.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. It lacks context such as prerequisites (e.g., requiring a page snapshot from browser_snapshot), exclusions (e.g., not for non-dropdown elements), or comparisons to siblings like browser_fill_form for general form input, leaving the agent to infer usage from the tool name alone.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations indicate readOnlyHint=true, destructiveHint=false, and openWorldHint=true, which the description doesn't contradict. The description adds valuable context beyond annotations by specifying it captures an 'accessibility snapshot' (implying structured data like ARIA roles or text content) and notes it can save to a markdown file via the filename parameter. However, it doesn't detail behavioral aspects like rate limits, authentication needs, or exact output format, keeping the score from being a 5.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that front-loads the core purpose ('Capture accessibility snapshot of the current page') and adds a comparative note ('this is better than screenshot'). There is no wasted text, and it effectively communicates key information in a compact form, making it easy for an agent to parse quickly.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity (1 parameter, no output schema), the description is reasonably complete. It clarifies the tool's purpose and distinguishes it from a sibling, with annotations covering safety and scope. However, it could be more complete by explaining what an 'accessibility snapshot' includes (e.g., HTML structure, ARIA attributes) or when to prefer it over other tools, slightly reducing the score.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema has 1 parameter with 100% description coverage, documenting that 'filename' saves the snapshot to a markdown file instead of returning it in the response. The description adds no additional parameter semantics beyond this, as it doesn't explain the filename usage or format further. With high schema coverage, the baseline is 3, and the description doesn't compensate with extra details.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool captures an accessibility snapshot of the current page, specifying both the action (capture) and resource (accessibility snapshot of current page). It distinguishes from the sibling 'browser_take_screenshot' by noting this is 'better than screenshot,' though it doesn't fully explain how it differs functionally. The purpose is specific but could be more explicit about what an 'accessibility snapshot' entails compared to a regular screenshot.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage by stating this is 'better than screenshot,' suggesting it as an alternative to 'browser_take_screenshot' for accessibility-focused captures. However, it lacks explicit guidance on when to use this tool versus others (e.g., for accessibility testing vs. visual documentation) or any prerequisites. The context is implied but not clearly defined, leaving some ambiguity for the agent.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide readOnlyHint=false, destructiveHint=true, and openWorldHint=true, indicating mutable and potentially destructive operations. The description adds value by specifying actions (list, create, close, select), which clarifies behavioral scope beyond annotations, though it doesn't detail side effects like what happens on close or creation defaults.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is extremely concise and front-loaded, listing all key actions in a single, efficient sentence with zero wasted words. It directly communicates the tool's capabilities without redundancy or fluff.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity (multiple actions, destructive potential) and lack of output schema, the description is minimally adequate. It covers what the tool does but lacks details on return values, error conditions, or interaction with browser state, leaving gaps for an AI agent to infer behavior.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with clear parameter descriptions (e.g., 'Operation to perform' for action, details on index usage). The description adds no additional parameter semantics beyond the schema, but the schema is comprehensive, so a baseline score of 3 is appropriate as it doesn't compensate unnecessarily.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose with specific verbs (list, create, close, select) and resource (browser tab), making it easy to understand what the tool does. However, it doesn't explicitly differentiate from sibling tools like browser_close or browser_navigate, which could handle similar operations.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides no guidance on when to use this tool versus alternatives. With siblings like browser_close (for closing) and browser_navigate (for creating/selecting via navigation), there's no indication of context, prerequisites, or trade-offs for choosing this multi-action tool over specialized ones.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, covering the safety profile. The description adds useful context about the inability to perform actions with the screenshot, which isn't captured in annotations. However, it doesn't describe behavioral aspects like what happens with permissions for element screenshots or how the tool handles errors.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences with zero waste. The first sentence states the core purpose, the second provides crucial usage guidance. Every word earns its place, and the structure is front-loaded with the most important information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a read-only tool with good annotations and full schema coverage, the description provides adequate context. It covers purpose and sibling differentiation well. The main gap is the lack of output information (no output schema and description doesn't mention what's returned), but given the tool's relative simplicity, this is a minor omission.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already documents all 5 parameters thoroughly. The description doesn't add any parameter-specific information beyond what's in the schema, but the schema provides complete coverage, justifying the baseline score.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the specific action ('Take a screenshot') and resource ('current page'), distinguishing it from sibling tools like browser_snapshot which is mentioned for actions. It provides a complete verb+resource+scope statement.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly provides when-not-to-use guidance by stating 'You can't perform actions based on the screenshot, use browser_snapshot for actions.' This clearly distinguishes this tool from its sibling and provides clear alternative usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description adds valuable behavioral context beyond the annotations. While annotations indicate destructiveHint=true (implying mutation) and openWorldHint=true (implying unpredictable environment), the description clarifies this specifically types text into editable elements, which helps the agent understand the scope of the destructive action. No contradiction with annotations exists.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is perfectly concise at 5 words, front-loading the core action ('Type text') and target ('into editable element') with zero wasted words. Every element earns its place in this minimal but complete statement of purpose.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (destructive browser interaction with 5 parameters) and the absence of an output schema, the description is minimally adequate. It states what the tool does but lacks information about return values, error conditions, or integration with other browser tools. The annotations provide safety context, but more behavioral guidance would be helpful.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 100% schema description coverage, the schema already documents all 5 parameters thoroughly. The description adds no additional parameter semantics beyond what's in the schema, so it meets the baseline of 3 for high schema coverage without providing extra value.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Type text') and target ('into editable element'), providing a specific verb+resource combination. However, it doesn't explicitly differentiate from sibling tools like browser_fill_form or browser_press_key, which might have overlapping functionality for text input scenarios.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

No guidance is provided about when to use this tool versus alternatives. The description doesn't mention when this tool is appropriate compared to browser_fill_form (for forms) or browser_press_key (for keyboard input), nor does it specify prerequisites like needing a page snapshot or element reference from browser_snapshot.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations provide readOnlyHint=true, openWorldHint=true, and destructiveHint=false, indicating a safe, non-destructive operation. The description adds behavioral context by specifying what the tool waits for (text appearance/disappearance or time), which isn't covered by annotations. However, it doesn't mention timeout behavior, error handling, or interaction with browser state, leaving some gaps in transparency.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, efficient sentence that directly states the tool's function without unnecessary words. It's front-loaded with the core action ('Wait for') and lists the three waiting conditions clearly. There's no redundancy or fluff, making it highly concise and well-structured for quick understanding.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's moderate complexity (3 parameters, no output schema) and rich annotations, the description is adequate but has gaps. It covers the basic purpose but lacks details on return values, error cases, or how it integrates with other browser tools. With no output schema, the description should ideally hint at what happens after waiting, but it doesn't, leaving completeness at a minimal viable level.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, with clear descriptions for all three parameters (time, text, textGone). The description adds minimal value beyond the schema by mentioning the parameters' purposes in a general way. Since the schema already documents parameters well, the baseline score of 3 is appropriate, as the description doesn't provide additional syntax, constraints, or usage examples.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose as waiting for text to appear/disappear or for time to pass, which is specific and actionable. It distinguishes itself from sibling tools like browser_click or browser_navigate by focusing on waiting/observation rather than interaction or navigation. However, it doesn't explicitly mention the browser context, which is implied but could be more precise.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description implies usage for waiting scenarios but doesn't explicitly state when to use this tool versus alternatives. For example, it doesn't clarify if this should be used before browser_click or after browser_fill_form. There's no guidance on prerequisites or exclusions, leaving usage context to inference rather than explicit instruction.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.