extract_devin_key

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

No annotations, so the description carries the full burden. It does add genuinely useful behavior: OS auto-detection and the concrete artifacts read (state.vscdb, credentials.toml). However, it says nothing about failure modes when no install is found, whether anything is written or cached, or that the returned value is a sensitive secret - meaningful gaps for a credential-extraction tool.

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?

A single front-loaded sentence states the action, source, and output with essentially no waste. The parenthetical alignment note is the only mildly extraneous element.

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?

With no output schema and no annotations, the description must cover the return value, and '输出有效凭据' is vague about whether it returns the raw key string, a structured credential object, or a path. It also omits error behavior when no local install exists, leaving the zero-param contract only partially specified.

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 tool takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description correctly conveys that the operation is fully self-configuring via OS auto-detection.

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 and resource: automatically extracting the Devin/Windsurf API key from a local installation, and it names the sibling implementation it aligns with (fast-context-mcp's extract_windsurf_key). It is clearly distinct from devin_status, devin_web_search and devin_web_fetch, though it doesn't explicitly contrast itself with them.

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 scope is implied by 'from a local installation' - use it when a local Devin/Windsurf install exists and you need its credentials - but there is no explicit when-to-use, when-not-to-use, or preferred-alternative guidance. An agent must infer the trigger condition from the resource name alone.

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