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

Annotations already declare the mutation profile (readOnly=false, destructive=false, idempotent=false, openWorld=false), so the bar is lower. The description adds genuine value beyond them by disclosing a failure mode and its error token: 'A similar open task is refused with duplicate_of', which tells the agent how to react to a rejected call.

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?

Two tight sentences, front-loaded with the core action and scoped with an inline example; the duplicate-refusal caveat follows and every clause earns its place.

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 4-param mutation with no output schema and only 25% schema coverage, the description covers purpose and the duplicate failure mode but leaves the enum semantics and body usage unexplained, so an agent must guess which kind to file.

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 only 25% (only 'project' is documented, with the list_projects hint). The description does not explain the 'kind' enum values (review/decision/verify/manual_action), the 'body' field, or title constraints, offering only an example title that hints at kind='verify'.

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 states a specific verb and resource: 'Add a to-do for the human to a project's manager-task list', with a concrete example of the kind of task. It is clearly distinct from list/dismiss/resolve/reopen siblings, though it never names an alternative to differentiate explicitly.

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?

Usage is only implied by the purpose statement; there is no explicit when-to-use, when-not, or alternative routing (e.g., vs. propose_milestone or resolve_manager_task). The duplicate-refusal note is behavioral, not a usage rule.

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