index_status

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the tool is clearly a safe read operation. The description adds valuable context by specifying exactly what metrics are reported (number indexed, number in cache, last rebuild time), which goes beyond the annotations. It does not contradict the annotations and provides helpful detail about the tool's output.

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, concise sentence that immediately states the core function. It is front-loaded with the action ('Report') and lists the three key metrics in a clear, organized manner. There is no redundancy or filler, making it highly efficient and well-structured.

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 simplicity (no parameters, no complex inputs) and the presence of an output schema, the description is complete. It explains what the tool reports without needing to describe return values (which are covered by the output schema). For a status-reporting tool with this straightforward scope, nothing essential 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, so the schema is trivially 100% described. The description does not need to explain parameters, and the baseline for zero-parameter tools is 4. The description focuses on the output, which is appropriate given there are no inputs to clarify.

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's purpose: reporting on fatwa index status, including counts and last rebuild time. It uses the specific verb 'report' with a clear resource 'index status', and it distinguishes itself from siblings like search_fatwas, list_sources, get_fatwa, and rebuild_index by focusing on status metrics rather than data retrieval or modification.

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 implies usage for checking index health and statistics, but it does not explicitly state when to use this tool versus alternatives. For instance, it doesn't mention 'use this before searching to ensure the index is up-to-date' or 'use this to diagnose why search results may be incomplete.' The purpose makes usage obvious, but there is no explicit guidance or mention of exclusions.

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