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

Annotations already declare readOnly, idempotent and closed-world, and the description reinforces with 'Pure computation: no network, nothing stored', which adds the no-storage guarantee. It goes well beyond the annotations by disclosing the trust model, the allowTest gating, and the epistemic limits of a verified result.

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 core action and the key/trust constraint are front-loaded, and each following clause (checks performed, required keys, allowTest, computation model, limitations) adds distinct value. Dense but not padded; slightly long for a single paragraph.

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 no output schema, the description responsibly explains what a verified result means and does not mean. The main gap is that two optional parameters (mode, known) have their semantics undefined anywhere in the definition.

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% across 5 parameters, so the description must carry more. It clarifies the two required parameters (bundle, keys with the JWKS trust-anchor meaning) and allowTest, but leaves mode ('archival' vs 'fresh') and known (up to 64 strings, presumably history anchors) unexplained even though 'history consistency' hints at it.

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 specific verb and resource ('Run the open Curbi Proof verifier (curbi.proof/0.1) on a bundle') and enumerates exactly what is checked: signatures, key windows, RFC 9162 inclusion under the signed log head, attestation binding and history consistency. This is clearly distinct from siblings like validate_policy or policy_check.

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 establishes the conditions for correct invocation: keys are required and are the trust anchor, embedded bundle keys are never trusted, and test keys only pass with allowTest. It also delimits what a passing result does not mean (provider action, authority), though it does not explicitly name a sibling tool as the alternative.

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