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 of behavioral disclosure. It mentions the tool 'understands test-to-source mapping,' which adds useful context about its intelligence beyond simple pattern matching. However, it doesn't describe other behavioral traits like performance characteristics, error handling, or output format. For a tool with no annotations, this is a moderate disclosure level.

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 extremely concise and front-loaded: two sentences that efficiently convey purpose and usage guidelines without any wasted words. Every sentence earns its place by providing essential information about what the tool does and when to use it.

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 tool's moderate complexity (3 parameters, no output schema, no annotations), the description is reasonably complete. It explains the tool's purpose and when to use it, but lacks details about output format or behavioral constraints. Since there's no output schema, the description could ideally mention what kind of results to expect, but it's still adequate for basic understanding.

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 all three parameters (symbol_id, fqn, file_path) with descriptions. The description doesn't add any parameter-specific details beyond what's in the schema. According to the rules, when schema coverage is high (>80%), the baseline score is 3 even with no param info in the description.

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 purpose: 'Find test files and test functions that cover a given symbol or file.' It specifies the verb ('find'), resource ('test files and test functions'), and scope ('cover a given symbol or file'). It also distinguishes from siblings by explicitly contrasting with 'Glob/Grep' tools, which suggests it's more intelligent about test-to-source mapping.

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 guidance: 'Use instead of Glob/Grep — understands test-to-source mapping, not just filename conventions.' This clearly indicates when to use this tool (for test coverage based on mapping) versus alternatives (Glob/Grep for filename-based searches), helping the agent choose appropriately among sibling tools.

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