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

Annotations already establish readOnlyHint=true, so the safety profile is covered. The description adds genuinely useful non-annotation context: the underlying endpoint (GET /api/v0/staff/{id}) and the response envelope ({ meta, response }), which matters because there is no output schema. It omits auth requirements, rate limits, and error behavior for an invalid id.

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?

Three short, front-loaded sentences with no filler: purpose first, then endpoint, then return shape. Slightly terse, but nothing is redundant and an agent can parse it in one pass.

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 two-parameter read tool with full schema coverage and a read-only annotation, the description covers purpose, target endpoint, and return envelope. The only meaningful gap is failure behavior (invalid/unknown id), which is minor at this complexity, and it usefully compensates for the absent output schema.

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 100%, so both the 'id' and 'fields' parameters are already documented in the schema, including the _fields syntax and '_ALL' option. The description only restates '{id}' in the URL template and adds no meaning beyond the schema. Baseline 3 applies.

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?

Starts with a specific verb+resource ('Fetch a single staff member'), and the word 'single' implicitly distinguishes it from the sibling list_staff. It never names the sibling explicitly, so the differentiation is left to inference rather than stated.

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 (retrieve one staff record when you have an id) but gives no explicit when-to-use, when-not-to-use, or alternative guidance. It does not tell the agent to prefer list_staff for enumeration or accelo_request for arbitrary endpoints, leaving routing to the reader.

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