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

Annotations declare non-readonly, non-idempotent, non-destructive, open-world. Description adds critical behavior beyond that: single-use nature ('A passport can only be claimed once'), ownership transfer, and side effect that 'Sentinel protection turns on.' Auth dependency also stated. Doesn't cover error/latency behavior, hence 4.

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?

Four sentences, front-loaded with purpose, then auth requirement, parameter conditions, and failure routing. Every sentence carries distinct information; 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 3-param mutation tool with no output schema, the description covers purpose, auth dependency, parameter conditions, irreversibility/one-time-use, and recovery path. An agent has everything needed to call correctly or route to refresh_claim_token.

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 100%, so baseline is 3. The description adds real semantics: session_token ties to auth_verify_otp for account binding, claim_token can be omitted when session already holds a pending claim, and the source of claim_token (claim_url). This meaning goes beyond the schema's field descriptions.

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?

States a specific verb (claim/attach) and resource (FLINT Agent Passport) with precise scope: 'attach an anonymously minted, unclaimed FLINT Agent Passport to an authenticated FLINT account.' Clearly distinguishes from siblings like issue_agent_passport and refresh_claim_token by naming those divergences.

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 routes to alternatives: 'if the token was already used or lost, call refresh_claim_token for a fresh one instead of trying to remint.' Also conditions claim_token omission. Gives when-to-use, when-not, and named alternatives.

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