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

With no annotations, the description carries the full burden. It implies a read-only operation ('look up') and enumerates the returned data. However, it does not disclose potential errors, rate limits, or what happens for unknown domains. It provides useful context but lacks depth.

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 immediately states the purpose and then lists the return values. Every word earns its place with no 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?

The tool has only one parameter and no output schema, but the description fully covers the expected return information (trust score, rating, count, rank, reviews), source, and operation. For its low complexity, the description is complete and sufficient.

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 coverage is 100%: the only parameter 'domain' has a clear description with an example. The tool description adds no additional semantic detail beyond what the schema already provides, so a baseline score of 3 is appropriate.

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 ('look up a domain') and the specific resource ('on truster.info'), and lists the exact data returned (trust score, average rating, review count, Tranco rank, recent reviews). This distinguishes it from the siblings search_domains (searching) and post_review (writing).

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: when you need trust-related details for a specific domain. However, it does not explicitly mention when to use this tool versus search_domains or post_review, nor does it provide any exclusion criteria. The context is clear but the guidance is only implied.

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?

With no annotations, the description fully carries the transparency burden and excels. It discloses authentication requirements, the AI-agent-generated label, the separate display section, and notably that the review does not affect human rating or trust score, which are non-obvious side effects.

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 three tightly worded sentences that lead with the core action, then detail authentication and key behavioral outcomes. It avoids redundancy and delivers maximum information in minimal space.

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?

The tool is simple with three well-defined parameters and no output schema. The description covers purpose, auth, and behavioral impact, providing all necessary context for correct invocation. No critical information is missing.

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 already provides complete descriptions for all three parameters (domain, rating, text) with 100% coverage. The description does not add any additional parameter semantics beyond the schema, so the baseline score of 3 is appropriate.

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 explicitly states 'Post a domain review on behalf of the authenticated user,' clearly identifying the verb, resource, and actor. It logically distinguishes from sibling tools (lookup_domain, search_domains) by focusing on the write operation.

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 clear context including the need for OAuth write scope and the authenticated user prerequisite. It does not explicitly name alternatives or exclusions, but the contrast with read-only siblings is implied by the tool's action and scope requirement.

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?

With no annotations, the description must carry the behavioral disclosure burden. It states that the tool returns trust score and review count for matches, which implies a read-only search operation. However, it does not discuss prerequisites, rate limits, exact match semantics, or what happens with no matches. Basic behavior is covered, but richer context is missing.

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 efficiently states the action, target, matching method, and return values. Every word earns its place; there is no redundancy or filler.

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 tool with one parameter and no output schema, the description adequately covers the core aspects: what it searches, how it matches, and what it returns. It mentions trust score and review count, which is sufficient for an agent to understand the tool's purpose. It lacks details on result formatting or edge cases, but these are minor for a simple search tool.

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 describes the sole parameter 'query' as 'Domain name or prefix', providing 100% coverage. The description adds the phrase 'by name prefix', which aligns with the schema but does not introduce additional meaning. Given the schema already documents the parameter, the baseline score of 3 is appropriate.

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 ('Search domains'), the resource (truster.info), and the scope ('by name prefix'), which distinguishes it from siblings like lookup_domain (likely exact match) and post_review (likely writing reviews). It also specifies the return values, making the purpose specific and unambiguous.

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 clear context for use: searching by prefix on truster.info. It does not explicitly mention alternatives or exclusions, but the sibling tool names imply a contrast with exact lookup and review posting. The prefix-searching condition gives enough guidance for when to choose this tool.

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