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

The annotations already declare readOnlyHint=true and idempotentHint=true, so the description only needs to add context beyond that. It adds a clear 'Returns' section describing the output structure (tags with IDs, titles, and method counts), which goes beyond what annotations provide. It doesn't cover pagination or errors, but for a simple read-only listing tool this is sufficient.

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 uses a clean structure with a short summary, 'When to use' bullets, a parameter list, and a returns section. Every section earns its place, with no fluff or repetition. It is concise yet complete, using clear headings and bullets for scannability.

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 a single parameter, no output schema, and read-only/idempotent annotations, the description provides everything an agent needs: what it does, when to use it, the parameter format, and the return value shape. There are no significant gaps. The complexity is low, and the description fully covers the 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?

The schema description for specId is minimal ('required,'), but the description enriches it by specifying 'The 32-character MD5 hash ID of the specification.' This gives concrete format details beyond the schema, adding real value. Schema coverage is 100%, and the description supplements it well, warranting a score above the baseline.

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 'Lists all tags across an entire API specification, spanning all collections.' This specifies a concrete verb (lists), a resource (tags), and a scope (entire API spec), and it distinguishes itself from the sibling tool tag_by_collection by emphasizing the global scope.

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 an explicit 'When to use' section with bullet points, including situations like wanting every tag or needing a global view. It also explicitly directs users to use tag_by_collection instead for single-collection queries, giving clear when-to-use and when-not-to-use guidance.

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