index_status

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

With no annotations, the description carries full disclosure burden. It details the entire return object structure, explains the embedding.status field and its error/not-loaded meanings, and mentions the limit of 10 failed files. This provides substantial behavioral context beyond a minimal 'get status' description.

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 well-structured: a one-line summary, then usage guidance, then return format. It is a bit long due to detailed return spec, but every sentence adds value, though slightly redundant given an output schema exists. Still, it remains concise and 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?

For a read-only status tool with no parameters, the description covers purpose, usage timing, return structure, and error interpretation. It even addresses diagnostic use cases and performance cost. This is fully sufficient for an agent to correctly select and invoke the tool.

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 tool has zero parameters, so the baseline is 4. The description doesn't need to explain parameters, and the input schema is empty. No gaps to compensate for, so the score matches the baseline.

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 reports index health and background indexing progress. It also provides specific usage scenarios (after add_folder/reindex and for diagnosing incomplete search results), which distinguishes it from sibling tools like search or reindex that have different purposes.

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 instructs when to use the tool: 'Use after add_folder or reindex to check whether indexing has finished, or to diagnose why search results look incomplete'. Also notes it's 'Cheap to call', setting expectations for frequent use. This is direct guidance on appropriate contexts.

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