index_info

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

There are no annotations, so the description carries the full burden of behavioral disclosure. The verb 'Report' and the listed fields strongly imply a read-only status operation with no side effects, which is adequate for a zero-parameter tool. However, it does not explicitly state read-only behavior or what happens if the index does not exist yet.

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 front-loaded sentence with a colon-separated list of report contents. Every word contributes information, and there is no redundant filler or repetition of the tool name.

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 low complexity, zero parameters, and presence of an output schema, the description is complete enough for an agent to invoke it correctly. It names exactly what status fields will be reported, and nothing else is required.

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 and the input schema properties object is empty, so there are no parameter semantics for the description to clarify. The zero-parameter baseline of 4 applies because the description needs no additional parameter detail.

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 uses the specific verb 'Report' with the resource 'vector store status' and enumerates concrete outputs: documents, chunk count, dimension, and FAISS index type. This clearly differentiates it from siblings like reset_index, index_document, and search_context, which perform different 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?

No explicit when-to-use or when-not-to-use guidance is provided, and no alternative tools are named. The intended usage is only implied: it is the obvious status-check tool among the siblings, but there is no suggestion about when to invoke it, such as before indexing or after a reset.

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