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

With no annotations, the description does real work: it discloses the lease-extension side effect, checkpoint persistence for dead-agent recovery, the required X-Queue-Key header, and a $0.001 x402 cost. It omits what happens if the lease already expired, whether calls are idempotent, and what the response contains, so the burden is only partly met.

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 purpose is front-loaded in the first clause, which is good. The trailing vendor/pricing parenthetical ('By OMENZ ... production: POST ... $0.001 via x402') is dense and partially noise, though it does carry environment and cost 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?

For a mutation tool with no annotations, no output schema, five mostly undocumented parameters, and zero required fields, the definition covers purpose, auth, side effects, and cost but leaves return shape, failure behavior, and parameter roles 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 description coverage is only 20%, so the description must compensate; it does partially by explaining the checkpoint payload ('e.g. a Locker id + step') and the x_queue_key header. The roles of item_id, queue_id, and worker_id remain undocumented in both schema and description, and the fact that nothing is required is unexplained.

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 action and resource: a worker heartbeat that 'extends its lease and stores a checkpoint ... for dead-agent recovery.' The verb-plus-effect phrasing distinguishes it from sibling mutations like queue_claim or queue_complete, though it never names an alternative 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?

The phrase 'worker is alive' implies the calling condition (periodic liveness signalling while holding a claim), but there is no explicit when-to-use/when-not guidance, no cadence advice, and no routing to alternatives such as queue_fail or queue_escalate for a dying worker.

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