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

Goes far beyond the annotations (destructiveHint=true etc.) by disclosing that values are encrypted and never returned, that the answer/list_modules only name variables, that backend modules restart while frontend modules rebuild, that platform variables are reserved, and that the operation is job-based with a per-module/per-project concurrency lock.

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-loads the core operation and then layers the important edge cases, though it is a dense run-on paragraph that could be split for readability. Every clause carries real information, so little 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?

With no output schema, the description fully covers the async return contract (job_id + get_job_status polling), the destructive/irreversibility caveat, and the failure modes, leaving nothing an agent needs to call it correctly unaddressed.

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 100% (both parameters documented), so the baseline is 3, but the description adds value beyond the schema: the set/remove/keep merge rule and the fact that values are encrypted and never returned, which shapes what the agent may expect back.

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 ('Set a module's environment variables') with the exact merge semantics, clearly distinguishing it from siblings like update_module or set_module_resources.

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 concrete operational guidance: poll get_job_status for the returned job_id, wait for the running job before retrying when refused, and retry during the update window. It names relevant siblings (get_job_status, list_modules) but does not explicitly contrast when to choose this over set_module_resources or update_module.

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