get_session_stats

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is fully covered. The description adds the specific data points returned (transfer totals, active torrent counts, speeds), which is useful behavioral context beyond the annotations. However, it doesn't disclose details like whether the stats are cumulative since session start, whether speeds are averaged or instantaneous, or any rate-limiting behavior. With annotations covering safety, a 3 is appropriate.

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?

A single, compact sentence that front-loads the verb and resource, then lists the three key data categories. Every word earns its place; there is no fluff or repetition of schema/annotation information.

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 zero-parameter, read-only tool with a rich output schema, the description is nearly complete. It tells the agent what data it will receive (transfer totals, active torrent counts, speeds). The only minor gap is not specifying whether these are session-wide aggregates or something else, but the tool name and sibling context (get_session) make that clear. The output schema likely details the return structure, so the description doesn't need to.

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 provides no parameter documentation. The description doesn't need to explain parameters, but it does clarify what the tool returns, which is the only semantic content an agent needs. With 0 params, the baseline is 4, and the description meets that baseline by clearly stating the output scope.

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 function: retrieving transfer totals, active torrent counts, and current speeds. It uses a specific verb ('Get') and names the resource ('session stats'), which distinguishes it from sibling tools like get_session (which likely returns configuration settings) and list_torrents (which returns per-torrent data). However, it doesn't explicitly name a sibling to differentiate from, so it doesn't earn a 5.

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 context: it's for getting aggregate session-level statistics rather than per-torrent or configuration data. However, it doesn't explicitly state when to use this tool versus alternatives like get_session or list_torrents, nor does it mention any exclusions or prerequisites. The context is clear enough for an agent to infer, but not explicitly guided.

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