code-fundi-auth-authenticate

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

Beyond the annotations (readOnlyHint=false, openWorldHint=true), the description reveals key behavioral details: it sends a 6-digit email OTP (not a magic link), the password is sent via X-CodeFundi-Auth-Password header, and on success the API key is configured in-memory for the MCP session only. It also notes the side effect of sending an email and the need for human interaction with the OTP.

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 slightly longer than the typical two-sentence ideal, but each sentence carries distinct information: endpoint, prerequisite, OTP flow, password mode, and session-scoped key storage. It is structured logically by mode and is front-loaded with the core purpose.

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 complexity of an authentication flow, the description is remarkably complete. It covers both authentication modes, the OTP delivery mechanism, the required next step (call verify), the header for password, and the session-limited key configuration. No output schema exists, but the description doesn't need to explain return values because the flow and side effects are clearly described.

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 baseline is 3. The description adds meaning beyond the schema by explaining how should_create_user relates to signup vs sign-in, clarifying that password is only used in password mode, and describing the behavior of auth_mode values. This enriches the parameter documentation, though the schema already provides adequate descriptions.

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 the tool's function: 'Start Code-Fundi authentication (POST /v2/auth/authenticate)'. It specifies the resource and action, differentiates from sibling tools like code-fundi-auth-verify (which is referenced as the next step), and covers both OTP and password modes.

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 provides explicit usage scenarios: 'Use auth_mode otp for new or returning users' with should_create_user true/false, and 'Password mode... should_create_user false for sign-in'. It also names the alternative/next tool (code-fundi-auth-verify) and states that no existing API key is required, giving clear context on when to use this tool.

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