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

Beyond the annotations (readOnly, idempotent, non-destructive), the description discloses specific safety behaviors: 'performs no arbitrary fetching, makes no contact request, changes nothing, and stores nothing.' It also enforces 'only stable Tier1 finding identifiers,' providing additional context about what the tool accepts.

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 description is compact (three sentences) and front-loaded with the core purpose. Every sentence adds value: purpose, usage, and safety. There is no redundancy.

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-parameter tool with a high-quality description, annotations, and an output schema, the description is complete enough. It explains what the tool does, when to use it, input restrictions, and side-effect profile, enabling correct invocation without additional information.

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?

With zero schema description coverage, the description compensates by explaining the purpose of findingIds: 'stable Tier1 finding identifiers' and specifying what not to submit. It does not detail the exact pattern or max items, but the schema already provides the pattern and constraints; the description adds semantic meaning beyond the syntactic schema.

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 verb ('maps') and resource ('stable Tier1 finding identifiers' to 'approved Tier1 services and public resources'), clearly distinguishing it from siblings like get_tier1_resource and score_it_health_check. It also communicates the scope ('only stable') and the context in which it is used ('after a Tier1 score or email-domain 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?

Explicit guidance is given on when to call the tool ('Call after a Tier1 score or email-domain check') and what inputs to avoid ('Do not submit prose, URLs, customer information, or invented identifiers'). This effectively differentiates it from alternatives and sets usage boundaries.

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