@git-fabric/chat

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

No annotations are provided, so the description carries the full burden. It describes the tool as returning aggregate stats for today, which implies it's a read-only operation (safe for monitoring). However, it doesn't disclose behavioral traits like rate limits, authentication needs, or whether the data is real-time vs. cached. The description adds some context but lacks depth for a tool with no annotations.

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 concise and well-structured: two sentences that efficiently state the tool's purpose and usage. Every sentence earns its place—the first describes the output, and the second provides context. There's no wasted verbiage, making it easy to parse.

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 complexity (simple read operation with no parameters) and lack of annotations/output schema, the description is moderately complete. It explains what stats are returned and their purpose, but without an output schema, it doesn't detail the return format (e.g., structure of the stats). For a monitoring tool, more specifics on output could enhance completeness.

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 0 parameters, and schema description coverage is 100% (since there are no parameters to describe). The description doesn't need to add parameter semantics, and it appropriately focuses on the tool's output. A baseline of 4 is applied as per the rules for 0 parameters, as the description compensates by explaining what the tool returns.

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: 'Return aggregate stats: total sessions, total messages, and tokens consumed today.' It specifies the verb ('return') and the resource ('aggregate stats'), including the specific metrics provided. However, it doesn't explicitly differentiate from siblings like chat_health or chat_session_list, which might also provide related metrics.

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 provides clear usage context: 'Useful for quota monitoring and observability.' This indicates when to use the tool (for monitoring quotas and observability purposes). It doesn't specify when not to use it or name alternatives among siblings, but the context is sufficient for basic guidance.

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