index_status

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

With no annotations, the description carries the full burden and does well: it explains freshness is keyed to the git commit, what 'stale' means, and the error condition when the semantic extra is not installed. It does not define 'model_mismatch' or discuss resource implications, which leaves a small transparency gap.

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?

Every sentence earns its place: purpose, freshness semantics, actionable usage guidance, then args and returns. It is front-loaded with the core question and uses clear formatting for skimming.

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?

There is no output schema, but the description lists all return fields (state, root, chunks?, indexed_at?, etc.) and the error form. Combined with usage guidance and error handling, a one-parameter status tool is fully covered.

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?

The input schema only declares root as a string, so the description's 'Absolute path to the repository' adds meaningful semantics. Since schema coverage is 0%, this compensation is important and mostly sufficient for a single parameter.

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 opens with a specific verb and resource: 'Report whether a repo's semantic index is fresh, stale, or absent.' It clearly distinguishes itself from sibling tools by framing it as a pre-flight check before using code_search or mr_review_context, and contrasts with index_repo which performs the indexing.

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 explicitly says 'Check this before leaning on semantic results (code_search / mr_review_context)' and instructs the agent to 'offer to index_repo(root) first' if state is stale or model_mismatch. This gives direct when-to-use guidance and names the relevant alternatives.

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