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

Adds substantial value beyond the annotations: it discloses irreversibility ('cannot be restored'), the exact blast radius (token, sessions, app sign-ins), what is NOT destroyed (owner balance and utilities), that repeat calls are harmless, and the specific failure mode returned when a keyed passport tries a token ('signature_required'). This is precisely the context an agent needs before a destructive call.

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?

Front-loads the irreversible consequence, then the reassurance, then the auth rules — the right priority order. Slightly dense in the final sentence and the balance/utilities reassurance is a touch wordy, but no sentence is filler.

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?

A zero-required-parameter destructive tool with no output schema: the description covers what happens, whether it can be undone, what survives, idempotency, and both auth paths including the error case. Nothing an agent needs before invoking 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?

Schema coverage is 100% and the single parameter is already documented, so the baseline is 3. The description still adds meaning by tying passport_token to the auth model and explaining the consequence of misusing it (signature_required), which the schema alone does not state.

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 and resource: 'End your passport for good', with the effect enumerated (token, sessions, app sign-ins stop). An agent immediately knows this is irreversible termination, not a suspension. It doesn't distinguish itself from the sibling remove_passport (which could plausibly read as a synonym) or rotate_token, which is the only meaningful ambiguity left.

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?

Gives concrete conditions and alternatives: an MCP-created (no key) passport may revoke itself with its own token as a kill switch, while a keyed passport must send a signed request. It also flags that the MCP app's own sign-in may already perform this, steering the agent away from redundant calls. No explicit guidance on choosing between revoke_passport and remove_passport.

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