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

With annotations only declaring the safety profile, the description carries real behavioral load: it explains that expires_at and grace_until are recalculated from the current time, that a shorter TTL can actually shorten the lease, that other members observe the new expiry, what stays unchanged (status, content, claimer, token), and what is returned (never a token). This is exactly the beyond-annotation context an agent needs for a non-idempotent mutation.

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?

Four front-loaded sentences with no filler; the recalc rule and the shrink caveat come first. There is mild overlap between 'the claim token stays the same' and 'never a token', which keeps it just short of a 5.

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?

An output schema exists, so return values need only light mention, and the description covers mutation semantics, immutability, and visibility thoroughly. It does not address failure modes (invalid or expired claim token), which is the only real gap for a four-parameter mutation tool.

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%, so the baseline is 3, but the description adds semantics the schema does not: that ttl_minutes is interpreted relative to the current time, that omitting it falls back to a default, and that it can shrink as well as extend the lease. That meaningfully disambiguates the TTL parameter's effect.

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 names a specific verb (extend/renew) and resource (your own claim lease on a task) and scopes it to 'your own' claim, which cleanly separates it from city_room_task_claim (which creates a claim) and city_room_task_release. An agent can pick it out of the 40+ siblings without opening the 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?

It implies the caller must be the existing claimer ('your own claim') and notes the TTL is 'allowed inside grace', which hints at the valid timing window, but it never states when to renew versus release or re-claim, nor what happens if the lease already expired. Usage is inferable rather than stated.

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