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

Annotations cover the safety profile (readOnlyHint=false, idempotentHint=false, openWorldHint=true), and the description adds the meaningful outcome that the user can then 'place orders from that restaurant'. It does not disclose failure modes such as an invalid or expired code, but it adds real domain context beyond the annotations.

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 tight sentences, front-loaded with the action and the key input source. No filler or 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?

With no output schema and full annotation coverage, the description supplies the essential missing context: the code's origin and the post-success state. A note on handling ambiguous clientId or failed/expired codes would make it fully 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%, so code, label, and clientId are already fully documented. The description only contextualizes the 'code' origin (browser address bar), which is marginally richer than the schema's 'redirect URL' wording; it says nothing about label or clientId. Baseline 3 applies.

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 ('Complete a sign-in') and explicitly ties it to the prior 'login' step, which distinguishes it from the sibling login tool. An agent can identify this as the second half of a two-step flow without opening the schema.

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 clearly states when to use it: after 'login', with the code the user copied from the address bar. It names the prerequisite tool but does not state exclusions (e.g. expired code, already-signed-in) or how it relates to switch_account/logout.

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