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

Annotations already cover read-only/idempotent/non-destructive, and the description goes well beyond them: it is free, it verifies signature/context/dates only, returns an incomplete status because verification is local, and requires an independently obtained registry rather than one accompanying the proof. These are meaningful behavioral traits an agent cannot get from the 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?

Four tight sentences, front-loaded with the core action and scope, then the input rule, then output semantics, then explicit exclusions. No filler; every sentence carries distinct 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?

Output schema exists so return structure needn't be restated, yet the description still explains the key result fields (receiptVerified vs incomplete status). Combined with the trust-independence rule and exclusion list, an agent has everything needed to call this 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 coverage is 100%, so the baseline is 3, but the description adds real semantic meaning: 'trust' must be independently sourced and not trusted merely because it accompanies the proof, and issuer/scope/chain are the explicit expected bindings. It clarifies intent behind the structured params rather than merely restating them.

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 verb+resource ('verification of a common Datoka proof') and the exact basis of verification (caller-supplied public trust registry plus explicit issuer/scope/chain). This clearly distinguishes it from sibling verify_agent_receipt and issue_proof_receipt without needing 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?

Gives a concrete input constraint ('Send only the proof, never raw documents') and explicitly bounds the operation ('No payment, factual accuracy or parent signatures are verified'), which tells the agent when this tool is not sufficient. It stops short of naming the alternative sibling tool to use in those cases, so it is slightly below the top tier.

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