live_start_scenario_run

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

With no annotations, the description carries full burden. It discloses that it returns immediately with a runId, does not wait, fails fast if the tab already has a run or single-step Play active, and requires the side panel open and connected. This provides useful behavioral context beyond the schema, though it doesn't mention any side effects or permissions.

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 three sentences with no filler. The main action and immediate-return behavior are front-loaded, and the contrast with the sibling and follow-up steps are succinctly stated.

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 no output schema and no annotations, the description covers the essential usage: how to start, that it's non-blocking, how to monitor progress, failure conditions, and prerequisites. It also references the session parameter implicitly by mentioning 'target tab'. Nothing critical is missing for an agent to call it correctly.

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 coverage is 60%, with descriptions for dataset, project, and session, but scenarioId and params lack descriptions. The tool description does not add any parameter-specific meaning beyond what the schema already provides, so it doesn't compensate for the uncovered parameters.

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?

States a specific verb 'starts' with a clear resource 'scenario' on the side panel's target tab, and contrasts with live_replay_scenario by noting it does not wait. This makes its purpose unambiguous and distinguishes it from the sibling.

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?

Explicitly names live_replay_scenario as an alternative and clarifies when to use this one (non-blocking). It also instructs to poll live_get_scenario_run or live_list_scenario_runs, and gives failure conditions and prerequisites, so an agent knows exactly when to choose this tool.

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