trace-mcp

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

No annotations are provided, so the description carries the full burden. It effectively discloses key behavioral traits: the tool lists keys with inferred types and formats, explicitly states it 'Never exposes actual values,' and clarifies it's for non-secret understanding of configuration. This covers safety and output behavior well, though it lacks details on error handling or performance limits.

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 front-loaded with the core purpose in the first sentence, followed by clarifying details. Every sentence earns its place by adding value: the first defines the action and scope, the second emphasizes safety constraints, and the third provides usage context. It is efficient with zero waste.

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 no annotations and no output schema, the description does a good job of covering the tool's behavior, safety, and usage. It explains what the tool does and what it avoids (exposing secrets), which is crucial for a tool handling sensitive data. However, it lacks details on output structure or error cases, leaving some gaps in completeness.

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 the schema already documents both parameters ('pattern' and 'file') with descriptions. The description does not add any additional meaning or examples beyond what the schema provides, such as clarifying how pattern matching works or file path requirements. Baseline 3 is appropriate as the schema handles parameter documentation adequately.

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 specific action ('List environment variable keys'), resource ('.env files'), and scope ('with inferred value types/formats'). It explicitly distinguishes this tool from potential alternatives by stating 'Never exposes actual values — only keys, types... and formats' and 'Use to understand project configuration without accessing secrets,' making its purpose distinct from tools that might expose sensitive data.

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 clear context for when to use this tool: 'to understand project configuration without accessing secrets.' It implies usage for safe inspection of environment variables. However, it does not explicitly name alternatives or specify when not to use it, such as compared to tools that might expose actual values or handle other configuration files.

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