index_repo

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 describes the multi-step process (fetching, parsing, extracting, saving) and mentions local storage persistence, which adds useful context. However, it lacks details on permissions, rate limits, error handling, or what happens if the repository is already indexed, leaving gaps for a mutation 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?

The description is a single, well-structured sentence that efficiently conveys the tool's purpose and key steps without unnecessary details. It is front-loaded with the main action ('Index a GitHub repository's source code') and every clause adds value, making it highly concise and clear.

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 complexity (indexing with AI options) and lack of annotations or output schema, the description is moderately complete. It outlines the process and storage outcome but omits details on performance, side effects, or return values. For a mutation tool with no output schema, more behavioral context would improve completeness, but it meets minimum viability.

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 thoroughly. The description does not add specific parameter semantics beyond what the schema provides, but since there are only 2 parameters and the schema is comprehensive, a baseline of 3 is appropriate. The description's mention of AI summarization aligns with the use_ai_summaries parameter, slightly enhancing understanding, warranting a 4.

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 with specific verbs ('index', 'fetches', 'parses', 'extracts', 'saves') and resources ('GitHub repository's source code', 'files', 'ASTs', 'symbols', 'local storage'). It distinguishes from siblings like get_file_outline or search_symbols by emphasizing the comprehensive indexing process rather than retrieval or search operations.

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 implies usage for initial indexing of a repository, but does not explicitly state when to use this tool versus alternatives like list_repos or get_file_tree. It mentions AI summarization as an option, which provides some context, but lacks clear guidance on prerequisites or exclusions compared to sibling tools.

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