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

With no annotations, the description provides useful behavioral context by specifying the output content (date + signal counts) and ordering (newest first). It does not mention side effects or auth, but the read-only nature of listing is implicitly clear, and the description adds meaningful disclosure beyond a simple 'list reports'.

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 sentence of 12 words, front-loaded with the tool's purpose. Every word contributes to clarifying what the tool returns and how it is ordered. No redundancy or filler.

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 simple list tool with one optional parameter and no output schema, the description covers the essential return shape (date + signal counts) and ordering. It does not explicitly explain pagination or full report content absence, but the mention of 'index' implies metadata-only. This is adequate given the tool's simplicity.

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?

Schema coverage is 100% (the only parameter 'limit' has a full description including default). The description does not elaborate on the parameter, but per the rubric, high schema coverage means the description need not compensate. Baseline 3 is appropriate.

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 it provides an 'Index of Orion's daily Celestia reports' with content specified as 'date + signal counts' and ordering 'newest first'. This distinguishes it from siblings like 'get_report' (fetches a single report) and 'search_reports' (searches), making the tool's purpose unambiguous.

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 the tool is for listing the report archive but does not explicitly state when to use it versus alternatives like 'search_reports' or 'get_report'. There is no 'when to use' or 'when not to use' guidance, leaving context to inference.

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