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

Annotations only declare readOnly=false, idempotent=true, destructive=false. The description adds substantial behavioral detail beyond them: concurrency locking semantics, the exact refusal signal, the coordinating tool (get_job_status), and update-window retry behavior. This is exactly the operational context an agent needs and cannot infer from annotations.

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 operation, then layered with constraints - every sentence carries actionable content (sibling contrast, concurrency rule, retry path, maintenance retry). It is dense with colons and semicolons, which slightly hurts readability, but nothing is wasted.

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 mutation tool with no output schema and full schema coverage, the description is complete: it covers what the operation does, its concurrency model, refusal handling, coordination with get_job_status, and maintenance-window retries. Nothing an agent needs to invoke it correctly is missing.

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 the schema already documents module_id (with list_modules pointer) and the replicas enum. The description's '1 or 2 pods' merely restates the enum range, adding no syntax or format detail beyond the schema. Baseline 3 is appropriate.

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+resource ('Run 1 or 2 pods of a module') and immediately names the sibling it contrasts with (freeze_module stops it). An agent can distinguish this from freeze_module, unfreeze_module, and set_module_resources without opening any 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?

Gives explicit when-to-use context: one operation per module and per project at a time, what happens on refusal (the refusal names the running job), and the prescribed recovery (wait via get_job_status, then retry). It also covers the maintenance-window case with the exact refusal string and retry delay.

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