Fetch

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint. The description adds meaningful context by disclosing that the result is 'a citable public summary' with limited fields (name, operator, location, status, market), making the tool's output expectations transparent. It does not mention rate limits or auth, but those are not central to this read-only operation.

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 two sentences long, front-loaded with the main purpose, and then adds an alternative and return shape in the second sentence. Every sentence earns its place with no fluff or repetition.

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 tool is simple (one required parameter) and has an output schema, so the description does not need to explain return values in depth. It covers when to use, what the result looks like, a limitation (summary vs. full specs), and directs to an alternative, making it complete for this scope.

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 with a clear description of the `id` parameter, including an example and its provenance from a prior search result. The description reinforces this by stating 'for an id returned by the `search` tool', but adds no new information beyond the schema, so the value is 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 uses a specific verb ('Fetch') and resource ('DC Hub record') and clearly states the input comes from the `search` tool. It distinguishes itself from sibling tools by explicitly directing users needing full structured specs to `get_facility`.

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 states exactly when to use this tool: 'for an id returned by the `search` tool'. It also provides an explicit alternative: 'For full structured specs use get_facility or open the url', giving clear when-to-use vs. 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.