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

Annotations declare readOnlyHint=true, so the safety profile is covered. The description adds behavioral detail: it compares against the previous version and returns a Markdown changelog, which is beyond the annotation. No contradictions or hidden side effects are disclosed, but the added context is meaningful.

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 fluff. The purpose, return format, and routing to the sibling tool are all front-loaded, and the prerequisite is stated last. Every sentence earns its place.

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 two well-documented parameters and no output schema, the description explains the return type (Markdown) and the comparison basis. It does not detail the changelog's internal structure, but that is not critical for invocation. The 'requires project context' hint is a minor gap but acceptable.

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 both parameters (specId and versionId) are already documented with their types and purposes. The description does not add any parameter-specific meaning beyond the schema, meeting the baseline of 3 for high 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 a specific verb (generate), resource (changelog for a specification version), and return type (Markdown). It also distinguishes itself from the sibling compare_versions by noting it provides a readable summary versus a raw structural diff, making it 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?

Explicitly instructs when to use this tool ('Use this for a readable summary of what changed') and names the alternative for the raw diff ('for the raw structural diff use compare_versions'). Also notes a prerequisite ('Requires project context'), giving agents clear decision criteria.

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