auth_login

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

With no annotations, the description carries the full burden of disclosing behavioral traits. It fails to mention whether a session/token is returned, side effects like session persistence, error behavior on invalid credentials, or any required preconditions. The minimal description provides zero transparency beyond the literal action.

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 and front-loaded, but under-specified. While every word earns its place, it lacks substance needed for a login tool. It is more an under-specification than a model of conciseness.

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 the lack of annotations and output schema, the description should explain the result of login (e.g., returns a token or user object) or clarify failure behavior. It does neither, leaving critical context missing for an authentication operation.

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?

The input schema already covers both parameters with clear descriptions (email and password), giving 100% coverage. The description merely repeats 'email and password' without adding semantic detail such as format, length, or which authentication flow is used. Thus it meets the baseline for high schema coverage.

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 states a clear action ('Login') and resource ('user') with credentials, but it does not differentiate from sibling tools like auth_signup or auth_logout. It is essentially restating the tool name with parameter context, lacking specific scope like session creation or token issuance.

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?

No usage guidance is provided. There is no mention of when to use this tool versus alternatives such as auth_signup for registration or auth_get_user for fetching user info. The description only implies login, leaving the agent to infer context.

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