fetch

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

No annotations are provided, so the description carries the burden. It discloses that the tool returns 'full contents' rather than partial data and mentions adherence to the OpenAI MCP specification, which offers some context. However, it does not address error behavior, permissions, or response structure beyond that.

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 concise with two short sentences. The first sentence states the core function efficiently, and the second adds a useful conformance reference. No filler is present, though the second sentence could be considered slightly vague.

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 simple single-parameter tool with no output schema, the description provides adequate information about what it does and the input. It mentions fetching 'full contents', which hints at the return value, but does not describe the exact response structure or potential errors. Given the low complexity, this is acceptable but not thorough.

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 already provides 100% coverage for the 'id' parameter with a clear description. The tool description adds the contextual detail that the ID belongs to a search result document, but this is a minor semantic addition; the schema already sufficiently defines the parameter.

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 fetches the full contents of a document by ID, using a specific verb and resource. It distinguishes itself from siblings 'search' and 'query' by focusing on retrieving a single known document rather than searching or filtering.

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 after obtaining an ID from a search result, giving clear context for when to use this tool. It does not explicitly mention alternatives or exclusions, but the 'by its ID' phrasing makes the appropriate scenario apparent.

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