auth_login

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

Annotations only mark this as non-read-only and non-destructive; the description adds the crucial behavioral fact that the call mutates session-wide state by installing a Bearer token for all later requests. It omits token lifetime/expiry and failure behavior, but the key side effect is disclosed.

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 short sentences with zero filler; the action is front-loaded and the consequence follows immediately.

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 login tool with a fully documented schema and no output schema, the description covers what the agent needs to call it and why. The remaining gap is disambiguation from the other sign-in tools in the sibling list.

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?

There is a single parameter with 100% schema description coverage ("GDEX API key (UUID format)"), so the schema carries the semantics. The description adds nothing about the key beyond what the schema already says, which matches the baseline of 3 for high 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 names a specific verb (authenticate) and the credential type (GDEX API key), so the agent knows exactly what this does. It does not, however, differentiate itself from sibling auth tools such as oauth_login, managed_sign_in, or generate_session_keypair.

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?

"Sets the Bearer token for all subsequent requests" implies this must be called before other tools, which is useful sequencing guidance. But it never states when to prefer it over oauth_login or managed_sign_in, nor what happens if called again with a different key.

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