Get build

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

Annotations already disclose the read-only, idempotent, non-destructive, and open-world nature of the tool. The description adds value by naming what the result contains (status, result, timing), but it does not go deeper into potential access requirements, response shape, or edge cases. With annotations carrying most of the safety behavior, 3 is appropriate.

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, well-structured sentence that front-loads the action, scope, and key output fields. There is no filler, and every clause contributes to understanding what the tool does.

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-resource fetch tool, the description plus schema fully covers the required inputs, the return focus, and the non-destructive behavior via annotations. No output schema exists, but naming status, result, and timing gives sufficient return-value context. Nothing critical is missing for an agent to call this correctly.

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%, and both parameters already have meaningful descriptions, including the buildId provenance from list_builds. The tool description primarily restates the id-based lookup and does not add substantial semantics beyond the schema, so the baseline of 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?

The description clearly states a specific verb ('Fetch'), a specific resource ('a single build / pipeline run'), and the retrieval key ('by id'). It also lists the key returned aspects (status, result, timing), and the 'single' qualifier distinguishes it from sibling list_builds without relying on the schema.

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 the right usage context: use this tool when you need one build identified by its id rather than a list of builds. It does not explicitly name alternatives or exclusions, but the id-based and single-item framing provides clear context. The schema's 'from list_builds' hint further reinforces the workflow.

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