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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds genuinely new behavior: only read-only public actions are ever called, non-called actions carry an explanatory reason, and mismatches between declaration and observed behavior are surfaced. This is real context beyond the structured fields.

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 dense sentences, front-loaded with what is returned, then verification behavior, then scope. Each sentence carries information, though the parenthetical enumerations make it slightly heavy.

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 does the work of explaining the return contents (declared capabilities, safety classes, confirmation status, mismatches) and the read-only calling policy. The only real gap is the undocumented domain parameter.

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 50%: verified_only is documented in the schema, but domain has no description anywhere. The description implies 'domain' is the lookup target but adds no format, defaulting, or semantics for either parameter, so it does not compensate for the coverage gap.

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 states a specific resource in detail: capabilities a domain declares (OpenAPI operations, MCP tools, A2A skills, API catalog entries), their safety classes, and which were actually confirmed. This is far more than a restated name, though it never explicitly contrasts itself with siblings like mcp_servers or public_counts.

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?

There is no when-to-use guidance, no alternatives named, and no exclusions. 'From the latest scan on file' hints that a prior scan is required, but nothing tells the agent when to pick this tool over its many siblings.

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