sfc_setup

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

With no annotations, the description carries the burden and does reasonably well: it discloses that this writes a file, that the file is private and local with a specific path, and adds a security constraint about not repeating credentials in chat. It omits write-side behavior an agent would want, such as whether an existing credentials file is overwritten and whether a confirmation is returned.

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?

Three short sentences, zero filler, with the core action and destination front-loaded before the security guidance. Every sentence earns its place.

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 four-parameter credential-write tool with no output schema and no annotations, the description covers purpose, storage location, and a key safety rule. Remaining gap is minor: overwrite semantics and any success/failure signaling are unstated.

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%, so all four parameters (appKey, token, userId, divisionId) are already documented in the schema. The description adds no further meaning about parameter formats or the optional divisionId default. Baseline 3 applies when the schema does the heavy lifting.

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 resource ('Save SFC API credentials') plus the exact destination path (~/.sfc/credentials.json), which is unambiguous. It does not explicitly differentiate from siblings like sfc_verify_credentials or sfc_credential_status, though the 'prefer env vars' line implies this is the one-time setup path.

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?

Gives a clear alternative ('Prefer MCP env vars when possible') that tells the agent when this tool is not the right choice, plus a security rule about not echoing credentials in chat. It stops short of naming the sibling tools (e.g. use sfc_verify_credentials to check saved creds) or stating prerequisites such as where to obtain the appKey/token.

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