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

With no annotations provided, the description carries the full burden. It discloses that the operation is free and that it returns the 'latest' skillcheck for an 'exact' bundle, but it does not mention error handling (e.g., invalid hash, no matching bundle), response format, or any side effects. It omits critical behavioral context an agent would need for robust invocation.

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, information-dense sentence. It front-loads the cost ('Free') and then states the core purpose and the exact input requirement. Every word contributes value; there is no redundancy or fluff.

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 and no output schema, the description adequately explains the input and the general behavior, but it does not specify what the tool returns (e.g., the skillcheck object, a status, or an error message). It also lacks guidance on edge cases like nonexistent bundles. Given the lack of an output schema, the description should have clarified the return value to be fully complete.

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 only provides a pattern for the parameter, but the description adds substantial meaning: it explains that bundle_sha256 is the SHA-256 of the canonical JSON of files sorted by path, each as {path, sha256}. This is a detailed semantic definition that goes far beyond the schema, giving the agent precise instructions on how to construct the input.

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 states a specific verb ('look up'), a resource ('latest skillcheck'), and a precise identifier ('bundle_sha256') with a detailed definition of that hash. It clearly distinguishes this tool as an exact-match lookup by hash, setting it apart from broader sibling tools like 'skillcheck' without needing explicit naming.

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?

There is no guidance on when to use this tool versus alternatives. It does not mention scenarios like 'when you have the exact bundle hash' or 'for fuzzy lookups use another tool'. The description is purely functional and offers no selection criteria or exclusions.

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