start_slice

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

Annotations declare only that this is a non-read-only, non-destructive, closed-world operation. The description adds meaningful behavior beyond that: the call is queued/detached, returns immediately rather than blocking, and completion must be observed via get_job. It omits timeout behavior, auth requirements, and what the job actually produces.

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 compact clauses, front-loaded with the action, then the async contract, then the one non-obvious parameter rule. No filler sentences and nothing that restates structured fields.

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?

With no output schema, the description correctly points to get_job for results, covering the return path. However, for a job-launching mutation tool it leaves too much unsaid: the meaning of revision, timeout_seconds, and what happens on timeout or failure.

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 0% across four parameters, so the description must compensate and largely does not. It only clarifies plate_index (0 = all plates, values are 1-based); revision, project_id, and timeout_seconds remain undocumented in both the schema and the description.

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?

"Queue a detached Studio slice" gives a specific verb (queue) and resource (Studio slice), and the async framing distinguishes it from synchronous siblings like open_in_studio. It never names a sibling alternative explicitly, but an agent can tell what operation this performs.

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?

"Returns immediately; poll get_job" clearly describes the async workflow and directs the agent to the correct follow-up tool, which is real usage context. There is no statement of when not to use this tool or what competing operation to prefer, so it stops short of a 5.

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