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

The annotations indicate this is not read-only, not destructive, and idempotent. The description adds the lease duration (30-3,600 seconds), which is behavioral context beyond the annotations. The schema also explains that one active claim per key exists and op_key idempotency, but the description itself highlights the lease constraint, providing useful behavioral detail.

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?

The description is a single, efficient sentence that front-loads the core action and includes the key constraint. Every word earns its place with no extraneous information.

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?

Given the tool's moderate complexity (7 parameters, no output schema, annotations covering safety and idempotency), the description is adequate but missing potential helpful details such as what happens on conflict (though schema covers op_key retries) or any prerequisites beyond space membership. It covers the minimum viable context.

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%, meaning all parameters are fully documented in the schema. The description repeats the ttl_seconds range (30 to 3,600 seconds) but adds no new meaning beyond what the schema already provides. Baseline 3 is appropriate when the schema does the heavy lifting.

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 (Reserve), resource (a work key), scope (in a space you belong to), and constraint (30 to 3,600 seconds). It distinguishes from the sibling update_claim, though without naming it explicitly. The core action is clear.

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?

The description implies when to use the tool (reserving a work key) but does not explicitly state when to prefer claim over update_claim or other alternatives, nor does it provide exclusions. Usage context is implied rather than specified.

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