Complete Authentication

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

The description adds context beyond annotations: it describes return values (account info or pending status) and the pending nature if user hasn't completed. Given readOnlyHint=false and destructiveHint=false, the description appropriately indicates a mutating but non-destructive operation.

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 concise with two clear sentences, an emoji for visibility, and labeled Args/Returns sections. No unnecessary information.

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?

Given one simple parameter and an output schema, the description fully covers the tool's purpose, prerequisite, and return possibilities. Complete for this complexity.

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 0% schema coverage, the description provides crucial meaning: it explains 'flow_cache' is the flow data returned from account_authenticate (the _flow_cache field). This clarifies the parameter's origin and type.

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 clearly states it completes device flow authentication, specifying the verb 'Completes' and the resource 'authentication process'. It distinguishes itself from sibling account_authenticate by referencing the prior step and the flow_cache argument.

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?

The description explains that it is used after the user enters the device code at the verification URL, and that flow_cache comes from account_authenticate. It implies a prerequisite but does not explicitly state when not to use or provide alternative tools.

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