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

Annotations already cover the safety profile (readOnly=false, destructive=false, idempotent=false, openWorld=false), and the description adds genuinely non-redundant behavior: one credit per new unique task with free lease reacquisition, a timed lease with reacquisition semantics, and the honest caveat that a lease cannot guarantee exactly-once external side effects. That cost and side-effect disclosure is exactly the value annotations cannot carry.

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 tightly packed sentences, front-loaded with the coordination purpose and lease behavior before retry mechanics. Every sentence carries information, though the density borders on telegraphic and could use a clearer separation of acquisition vs. retry guidance.

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?

With an output schema present, return values need not be explained, and the description covers cost, lease timing, retry semantics, and the side-effect caveat. Remaining gaps are minor: what happens when a lease expires unrenewed and the conflict/409 path are left to the schema and sibling tools.

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 goes beyond the schema by explaining the reuse-vs-fresh idempotency_key decision (replay an active acquisition with the same key, use a new key for a later acquisition). It adds little about task_key, namespace, worker_id, or lease_seconds beyond what the schema already documents.

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 precise verb pair and resource: it acquires a timed lease or retrieves an existing reservation/result for a shared task. The framing around coordinating independent agents on a shared account/namespace/task key makes it clearly distinct from siblings like get_task, renew_lease, or release_lease.

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 states the operating context (independent agents sharing account, namespace, and stable task key) and gives explicit retry guidance: reuse idempotency_key to replay an active acquisition after a lost response, use a fresh key for a later acquisition. It does not name sibling alternatives (e.g., get_task for status checks) or state when not to claim, so it stops short of a 5.

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