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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It discloses the AUTH requirement, the freezing of a canonical sha256 commitment, and the obligation to close the attempt. It doesn't detail failure modes or side effects of not closing, but the disclosed traits are significant and non-contradictory.

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 two sentences and conveys all necessary information: auth, timing, the action of freezing a commitment, and the closure condition. Every phrase contributes meaning with no redundancy or filler.

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 complexity (6 parameters, nested objects, no output schema, no annotations), the description provides essential workflow context about preregistration, commitment, and closure. The schema covers parameter specifics. It doesn't explain return values, but no output schema exists, and the lifecycle is sufficiently clear for an agent to use it correctly.

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 100%, so the schema already documents all six parameters. The description adds context about the manifest's role (the exact object to later file) and the commitment mechanism, but it doesn't provide additional detail on parameter formats or relationships beyond the schema. This aligns with the baseline of 3 for high schema coverage.

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 clearly states the tool's purpose: 'preregister one measurement attempt BEFORE reader spend.' It specifies the action (preregister), the resource (a measurement attempt), and the timing, distinguishing it from siblings like submit_measurement and abort_attempt. The mention of a canonical sha256 commitment further clarifies the unique function.

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 explicitly indicates when to use this tool ('BEFORE reader spend') and describes the required lifecycle: 'A completed measurement or an evidenced abort must close the attempt.' While it doesn't explicitly name alternative tools, the workflow implies that submit_measurement or abort_attempt are the subsequent steps, making the usage context clear.

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