fetch_trace

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

No annotations are provided, so the description carries the full burden. It conveys a read-only inspect operation and specifies what 'full details' means (input, output, all observations). It does not mention any side effects or edge cases, but for a simple read tool this is sufficient, though not exhaustive.

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 sentences, no filler. The opening sentence states the core action, and the subsequent sentences provide usage context and an alternative. Every sentence earns its place.

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 single-trace fetch tool with an output schema and a simple parameter set, the description covers the essential context: what it returns, when to use it, and how it differs from the listing tool. The only gap is the undocumented 'project' parameter, but overall it is sufficiently 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?

Schema description coverage is 0% and the description only implicitly references trace_id ('when you have a trace ID'). The optional 'project' parameter is not explained at all. Since coverage is zero, the description should have compensated by explaining parameters, but it only partially does.

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 gets full details of a single trace, including input, output, and observations. It explicitly contrasts with sibling tool fetch_traces for listing traces, making the purpose distinct.

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?

Provides explicit guidance: 'Use this when you have a trace ID' and names the alternative 'fetch_traces' for listing. This clearly communicates when to use this tool versus the most likely sibling.

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