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

Annotations already declare non-read-only, non-idempotent, open-world, non-destructive behavior. The description adds value beyond that by disclosing the credit cost ('spends credits for the steps it executes') and the shape of the immediate return (run_id, workflow_id, initial status), which signals asynchronous execution rather than a completed result.

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?

Four short sentences, front-loaded with purpose and followed by input handling, return value, and cost. Every sentence carries distinct information with no repetition of the name or schema.

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 two-parameter execution tool with no output schema, the description covers the trigger input, the returned identifiers, and the credit cost, which is enough to call it correctly. It does not say how to follow up on the run (e.g. checking status via alterlab_job), which would complete the picture for an async operation.

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 100%, so both parameters are already documented. The description adds only a small clarification that input_data feeds the 'webhook trigger node' and that it is optional; workflow_id gains no meaning beyond the schema. Baseline 3 applies when the schema carries the parameter burden.

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 and resource: 'Start an execution of a workflow you saved in the AlterLab dashboard.' This is unambiguous and, unlike the sibling tools (scrape, crawl, search, job, schedule), clearly identifies a workflow-execution action, so an agent can select it without opening the schema.

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 phrase 'a workflow you saved in the AlterLab dashboard' establishes the prerequisite that the workflow must already exist, which is useful context for invocation. There is no explicit when-not-to-use guidance or reference to an alternative sibling (e.g. polling with alterlab_job), 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.