code_search

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It explicitly states that the tool returns 'relevant code snippets with file paths and line numbers' and describes supported filters, which conveys a read-only, non-destructive behavior. It does not mention any side effects or limitations, but for a search tool this level of detail is adequate.

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 compact and efficient, consisting of two sentences that front-load the primary action with examples, then cover the return format and filters. There is zero filler, and every sentence contributes to the agent's ability to invoke the tool correctly.

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?

Since there is no output schema, the description appropriately explains the return value ('relevant code snippets with file paths and line numbers'). It also covers all parameters implicitly through the filtering descriptions and the query example, making the tool fully usable without needing to inspect the schema or other sources.

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 every parameter. The description adds minimal extra meaning beyond what the schema provides—it merely echoes the filtering options (directory path, language, codeOnly) without introducing new syntax or details. This is the baseline score for high schema coverage.

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 a specific verb ('search'), a resource ('the codebase'), and a method ('semantically'), with concrete examples of natural language queries. It also differentiates from sibling tools by implying this is the actual search operation, while siblings are status, reindex, and guide tools.

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 the tool (searching the codebase semantically) and mentions filtering options that shape usage. It does not explicitly name alternatives or state when not to use it, but the sibling tools are so distinct (status, reindex, guide) that exclusion guidance is not strictly necessary.

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