computeruse_start_session

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

With no annotations, the description carries the full burden and does well by explicitly disclosing side effects: creating/overwriting sessions/active_session.json and adding a history row to SQLite. This tells the agent the operation is persistent and state-changing, which is essential for a session-start tool.

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 compact: two sentences with no filler. The main purpose is stated first, followed by the key side effects, making it easy for an agent to quickly grasp the tool's behavior.

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 session-start tool with no output schema, the description covers purpose and critical side effects. It could add a note that this should be called before other session tools, but the tool name and sibling context make that reasonably inferable.

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 both 'task' and 'agent_name' are already documented in the input schema. The description does not add extra semantics beyond restating that the session is for an external agent task, which is sufficient for a baseline score.

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 states a specific action ('Start') on a specific resource ('tracked ComputerUse session') and explains its core effect. It is clearly distinct from sibling tools like computeruse_finish_session or computeruse_execute_step.

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 makes the usage context clear: this is for initiating a tracked session for an external agent task. It does not explicitly contrast with alternatives, but the start-vs-finish relationship with siblings is strongly implied by the tool name and wording.

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