eas_build_start

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

With no annotations, the description carries the behavioral burden and does well: it states the call is non-blocking ('does NOT block'), gives the expected 10-40 minute duration, and names the artifact needed to continue (build_id). It omits prerequisites such as authentication/credentials and that a build is a costly, side-effecting operation that is not trivially reversible.

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?

Front-loaded with the core action and its non-blocking nature, followed by just enough follow-up (duration, status hand-off) and one line of parameter hints. No filler sentences.

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?

An output schema exists, so return values need not be explained, yet the description still usefully points to build_id as the tracking handle. For a mutating, long-running tool with no annotations, the only meaningful omission is auth/credential prerequisites.

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 coverage is 0% and there are no enums, so the description must compensate, and it largely does: it enumerates valid platform values (ios, android, all) and defines profile as a profile from eas.json. project_path is left undocumented, which is the one remaining gap for a required 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?

States a specific verb and resource ('Start an EAS build') plus the key behavioral fact that it returns immediately. An agent can distinguish it from eas_build_list, eas_build_status and eas_build_download without opening a 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?

Explicitly routes the agent: after starting, track progress with eas_build_status using the returned build_id. This is a clear hand-off to the correct sibling, though it gives no guidance on when a build should be initiated vs. other lifecycle steps (e.g., eas_submit).

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