trw_code_index_update

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

No annotations are provided, so the description bears full responsibility for behavioral disclosure. It mentions 'update' but does not clarify whether the operation is destructive, idempotent, or what side effects occur (e.g., disk writes). Missing details about safety, permissions, or concurrency risks 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?

Two sentences with no wasted words. The first sentence names the action and object (the manifest), and the second provides concrete usage guidance. Perfectly 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?

The description explains why to use it and when, but given no output schema and lack of annotations, it omits behavioral context like idempotency, prerequisites (e.g., repo_root validity), and how paths affect the index. Schema descriptions help, but the overall completeness is average for a tool with three parameters.

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%, setting baseline at 3. The description adds no extra meaning beyond the schema; it only names the tool's purpose. The parameter descriptions in the schema already explain force, paths, and repo_root 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 explicitly states it updates a 'local SHA-256 code-index manifest' and specifies its use case: 'before code search or symbol analysis without returning file bodies.' This clearly distinguishes it from siblings like trw_code_search and trw_code_symbol, which operate on the index instead of updating it.

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 tells when to use the tool ('before code search or symbol analysis'). It implies an ordering dependency but does not explicitly state when not to use it or mention alternatives. Given sibling names, the context is sufficient but could be more precise.

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