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

Annotations only say non-read-only, non-destructive, idempotent; the description goes far beyond with lease expiry semantics (10 minutes, self-lapsing so a crashed agent cannot block a task), all three return shapes including the already-DONE case, the fact that a lease grants no permission, and the exact permission requirements (task.edit.any / task.edit.own).

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 purpose and the mutual-exclusion rationale, then layers return values, lease lifecycle, related tools, and permissions in a compact sequence. Every sentence carries distinct information; none is filler.

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?

There is no output schema, so the description must carry return values, and it does so completely (claimed true/false, competing agent, DONE status with change time). Combined with lifecycle, alternatives, and auth, an agent has everything needed 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 coverage is 100% and the schema already documents ttlMinutes with its default of 10 and cap of 60. The description's mention that it 'sets a different lifetime' adds no syntax or constraint detail beyond the schema, so the baseline 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?

States a specific verb and resource ('Take an exclusive execution lease on one task') with the exact scope and motivation ('so a second agent on the same board does not do the same work'). It explicitly separates itself from assign_task, which an agent might otherwise confuse with claiming work.

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 ('before working on it'), the ongoing cadence ('call renew_task_lease about every 3 minutes'), the termination step ('release_task when finished'), and the alternative for a different need ('use assign_task for ownership'). Nothing about routing between siblings is left to inference.

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