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

Annotations already indicate destructive behavior (destructiveHint: true) and non-read-only status (readOnlyHint: false). The description adds no extra behavioral context, such as side effects on external systems, authentication requirements, or rate limits. It does not contradict annotations, but also does not enrich them.

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 conveys the core purpose. It contains no fluff or redundant information, and every word contributes to explaining what the tool does.

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 executes arbitrary API requests, but the description does not mention what the response looks like, error behavior, or potential side effects beyond what annotations hint. Since there is no output schema, the description should at least indicate that a response is returned. The schema covers parameters, but the overall context for an agent is incomplete.

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 detailed descriptions for parameters including the HAR request object's subfields (method, url, postData variants, etc.). The tool description itself adds no parameter-specific meaning, but the schema already provides strong semantics, 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 tool's function: 'Executes an API request with a given HAR request object.' This uses a specific verb ('executes') and resource ('API request') and distinguishes it from sibling tools that focus on listing/searching endpoints rather than making actual calls.

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 the tool is for executing API requests, but it does not explicitly state when to use it versus alternatives. The only related guidance is in the schema's title parameter, which mentions using 'list-specs' or 'search-endpoints' to see available specs—this is more about parameter resolution than tool selection.

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