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

Annotations already indicate read-only, open-world, idempotent, non-destructive behavior. The description adds valuable context beyond annotations: rate limits (25 calls/day per client IP), sharing of quota with /demo/v1/* routes, reset time, and version-resolution behavior when a version is given. No contradictions with 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 compact: two sentences with the core purpose first, then usage limits and paid upgrade path. No redundant filler, and each sentence delivers distinct information (function, quota, alternative).

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 presence of an output schema covers return values, so the description focuses on purpose, quota, and version resolution. However, it omits explanations for the ecosystem/package parameters and doesn't mention any prerequisites or relationship to sibling tools. For a simple lookup tool with good annotations, this is moderately complete 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?

Schema description coverage is 0%, so the description must compensate. It adds meaning for 'version' ('resolved at a pinned version when given') and implies 'symbol' is the target, but it does not clarify the 'ecosystem' enum values or the 'package' parameter. This leaves half the parameters under-explained.

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 returns 'Exact signature, structured params, docstring summary, and deprecation status for one symbol', which is a specific resource and scope. It distinguishes itself from siblings (package_exists, symbol_exists, version_diff) by describing a detailed signature lookup rather than existence or diff checks.

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 (resolve a symbol's signature, especially with a pinned version) but does not explicitly compare against sibling tools or state when to prefer this over symbol_exists or version_diff. It provides context about rate limits and paid alternatives, but not tool-selection guidance.

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