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

With no annotations, the description must carry behavioral disclosure. It states the verification pipeline and return categories, but leaves unaddressed whether the operation is read-only, contacts an external UTA service, stores the credential, or has failure modes. This is adequate but has clear gaps.

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?

Two sentences with no filler: the first names the action and scope, the second names the outputs. Key format information is front-loaded before the return value list.

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?

For a single-required-parameter tool, the description covers input type, supported formats, pipeline, and output categories despite having no output schema. It would be more complete with error behavior or response structure, but nothing essential for selecting and invoking it is missing.

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 defines credential as a JSON string or JWT at 100% coverage. The description adds value by listing the concrete supported credential types (W3C VC, MCP Card, ATC v3, A2A, EAT-AI, ZTA, X.509), which helps agents prepare valid inputs.

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?

Description names a precise operation ('verify'), a specific resource class ('AI agent credential'), and enumerates accepted formats, then states the outputs. This clearly differentiates it from siblings like marketnow_translate_credential and marketnow_check_domain.

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 phrase 'Verify any AI agent credential' gives clear context for when to call. It does not explicitly name alternatives or exclusions, so it stops short of a 5, but the verify-versus-translate contrast with siblings makes the intended use unambiguous.

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