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

The description discloses key behaviors beyond the annotations: the receipt is idempotent, Ed25519-signed, and commits to specific elements (HASHED inputs, sources, snapshot checksum, retrieval times, decision states). It also explicitly scopes the attestation as evidence only, not a clearance or legal determination. This adds substantial value beyond the readOnlyHint and destructiveHint annotations.

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?

Three sentences, each earning its place. The description front-loads the core function, then adds crucial limitations in a compact form. No repetitive or vague language.

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 rich annotations, full schema coverage, and presence of an output schema, the description fully covers the tool's purpose, behavioral constraints, and parameter semantics. It also explains the receipt's evidentiary scope and exclusions, making it complete for an agent to select and invoke 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?

The schema already provides 100% coverage for both parameters, but the description enriches the 'bundle' parameter by naming additional contents (snapshot checksum, retrieval times) and reinforcing the 'no raw PII' constraint. This goes beyond the schema's brief description, adding meaningful semantic detail.

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 uses a specific verb ('Bundle... into... receipt'), names the resource (screening checks), and clearly distinguishes this tool from siblings by focusing on creating a signed receipt rather than screening or listing. It also clarifies what the receipt is not (a clearance or legal determination), leaving no ambiguity about its purpose.

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: when you need provable evidence of what was screened and when, in the form of a signed receipt. It includes strong exclusions ('not a clearance', 'not a legal/compliance determination') but does not explicitly name an alternative tool or contrast it with siblings, so it falls just 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.