index_codebase

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

No annotations, so the description fully covers behavior: it creates vector embeddings for 50+ languages and mentions the initial indexing vs incremental nature, though it could clarify re-indexing implications.

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 sentences, each carrying essential information: purpose, usage priority, and alternative tool suggestion. No redundancy, front-loaded.

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?

Covers purpose, usage, and high-level behavior (vector embeddings). Lacks details on return value or error handling, but sufficient for an indexing action given no output schema.

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 coverage is 100%, so description adds minimal value to parameter understanding. The description does not elaborate on individual parameters beyond schema defaults.

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 indexes a codebase for semantic code search, specifying it is a prerequisite for search_code and distinguishing it from sibling tools like search_code and update_index.

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?

Explicitly states when to use ('USE THIS FIRST before search_code'), that it is required once per project, and directs to use update_index for incremental updates, providing clear alternatives.

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