Summarise logs into message patterns

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

With no annotations, the description carries the full burden. It discloses that the tool runs over a random sample and that counts are approximate, which is a critical behavioral trait. However, it does not explicitly state that the operation is read-only, nor does it describe output structure, permissions, or timeout behavior beyond what the schema already notes.

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?

Three sentences, each earning its place: the core transformation, the intended questions it answers, and the critical sampling caveat. It is front-loaded with the action and avoids redundant or promotional language.

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 tool with 5 optional parameters and no output schema, the description covers the primary use case, the key behavioral caveat about sampling, and what kind of result to expect ('short list' with counts). It could mention exact output shape or edge cases, but schema descriptions fill most parameter-level gaps.

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 100%, so the parameters are already well documented. The description adds context about sampling and approximate counts, which relates to probability, but it does not significantly extend the schema's parameter-level guidance. A baseline of 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 opens with a specific verb and resource: 'Collapse a window of raw log lines into the handful of message templates behind them, with a count for each.' It clearly distinguishes itself from search/count siblings by framing the use case as answering 'what is in these logs' or 'what changed' without reading individual lines.

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 explicitly says when to use it: to summarize logs into patterns and answer high-level questions about content or changes. It does not mention when not to use it or name alternative tools, but the context is clear enough to route an agent appropriately.

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