index_coherence

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

With no annotations provided, the description carries the full burden and does well: it explicitly states 'Read-only' and enumerates the specific dimensions of coherence checked. It does not cover authentication, rate limits, or failure behavior, but for a zero-parameter read-only diagnostic, the disclosed scope is sufficient.

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 compact and front-loaded: the headline question communicates the core purpose, followed by the concrete report items and the motivating scenario. Every sentence earns its place, and 'Read-only' is a useful final note.

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 zero-parameter diagnostic tool with no output schema, the description is complete: it defines what coherence means, what conditions trigger the check, and why an agent should care. No critical calling information is missing.

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 schema is empty, so there is nothing for the description to clarify about parameter meaning. The baseline of 4 applies because the absence of parameters removes any semantic burden from the description.

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 pointed question and then specifies exactly what the tool reports: active text records missing a vector, recipe vs embedder mismatch, and persistence regime. This clearly distinguishes index_coherence from the many sibling diagnostic tools by tying it to a deterministically detectable lagging-index condition.

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 gives a concrete scenario for when to use the tool: a governed store serving stale answers through a lagging index, and it labels this tool as the deterministic check for exactly that. It does not explicitly name alternatives or exclusion criteria, but the usage context is clear.

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