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

Annotations already declare readOnly and idempotent. The description adds critical context: runs client-side, zero PII, zero network, renders interactive widget. This goes well beyond annotations, providing full disclosure of behavior.

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 densely informative sentences with no wasted words. Front-loaded with the purpose, then usage, then behavioral details. Perfect structure.

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?

Covers purpose, usage, behavioral traits, and parameter semantics. Output schema exists so return values need not be described. A minor gap: the term 'AINumbers tool' is not explained, but given the sibling 'list_ainumbers_tools', it's likely known. Overall very complete.

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%; baseline 3. The description adds meaning by explaining that inputs come from the manifest input_schema and are applied via AIN Bridge prefill, clarifying the parameter's role beyond the schema description.

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 specific RFC validations (9728, 8707) and risk assessment (token-passthrough/confused-deputy), clearly distinguishing it from siblings like 'audit_mcp_tool_scope_revocation' and 'validate_mcp_authorization_metadata'.

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?

Explicitly states 'Use when a developer is securing an MCP server's authorization,' providing clear context. Could be stronger by explicitly noting when not to use it or comparing to related siblings, but the guidance is effective.

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