CountTool

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

With no annotations provided, the description bears the full burden of behavioral disclosure. It only states that it returns a count, without addressing read-only nature, authentication, rate limits, side effects, or the query's impact. The description is insufficient for an agent to understand the tool's behavior.

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 with no wasted words. However, it omits critical information that could be added without sacrificing conciseness, such as parameter guidance or query format hints.

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, lack of annotations, 50% schema coverage, no output schema, and multiple sibling tools, the description is too brief. It fails to explain the expected query structure in 'body', how to specify the index, or the return format (e.g., integer). This leaves the agent underinformed.

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 description coverage is 50% (only the 'body' parameter has a vague description, 'index' has none). The tool description adds no parameter details, leaving the agent to guess the expected structure for 'body' and the role of 'index'. This is insufficient, especially given the lack of enum or output schema.

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 that the tool returns the number of documents matching a query, which aligns with the tool name 'CountTool'. It distinguishes itself from sibling tools like SearchIndexTool by focusing on count rather than document retrieval, but could be more specific about the query format (e.g., JSON query).

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 guidance is provided on when to use this tool versus alternatives such as SearchIndexTool or ExplainTool. There is no mention of prerequisites, when not to use it, or how it compares to sibling tools, leaving the agent without decision-making support.

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