Finish MyAnimeList login

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

Annotations already indicate readOnlyHint=false and openWorldHint=true, so the agent knows it's a mutation with external side effects. The description adds context that it's an OAuth callback, but does not elaborate on specific side effects, failure modes, or required permissions. This is adequate but not exemplary given 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?

The description is two sentences: first states what the tool does, second provides usage guidance and input format note. Every sentence is functional with no wasted words, making it efficiently front-loaded.

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 simple OAuth callback tool with one required parameter and a known output schema, the description covers purpose, usage context, and input format. It does not need to explain return values as an output schema exists, making it complete for the complexity level.

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%, and the tool description merely rephrases the schema's parameter description ('by submitting the URL... or a bare code string'). No additional meaning is provided beyond what the schema already offers, so baseline 3 is appropriate.

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 that the tool completes a login initiated by login_mal by submitting the redirect URL. It uses specific verb+resource ('complete login'), and distinguishes from the sibling tool login_mal, which starts the login.

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 explicitly says 'Use this when login didn't complete automatically — e.g. the server runs on a remote/headless host.' This provides clear context for when to use the tool versus alternatives, and implies it should not be used when login completes automatically.

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