complete_login

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

Annotations declare readOnlyHint=false and openWorldHint=true, so the agent already knows this is a state-changing, external-facing call; the description does not contradict that and usefully adds the exact redirect URL format expected. It says nothing about what happens on an expired or invalid code, whether a session/token is established, or how failure surfaces — meaningful gaps for an auth-completion step.

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?

A single sentence with the action front-loaded and the critical format detail in a parenthetical example. Nothing is wasted and nothing essential is buried.

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 one-parameter tool with no output schema and no nested objects, the description covers the input adequately. It is thin on flow context — the agent must guess that a login must be in progress and cannot tell what a successful completion yields.

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 0%, so the description must carry the parameter, and it does: it explains that redirect_url is the full URL the browser ended on and gives a concrete shape with the code query parameter. Remaining ambiguity is minor, e.g. whether the URL must be byte-identical to the registered redirect URI.

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 outcome ('Finish sign-in') plus the exact mechanism ('passing the full URL the browser ended on'), which separates it from the sibling 'login' (start) and 'login_status' (check). It stops short of naming those siblings explicitly, so it is clear but not fully differentiated in-text.

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 word 'Finish' and the reference to 'the browser ended on' imply this is the post-redirect step of a flow begun elsewhere, and the required URL shape is given. There is no explicit statement of prerequisites (e.g. an in-progress login), when not to call it, or how it relates to 'login_status', so usage must be inferred.

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