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

Annotations already declare readOnlyHint=false, idempotentHint=false, so a run is expected to be a non-idempotent, mutating action. The description adds behavioral details (synchronous run, return outcome and trace_summary) but does not explicitly warn about potential side effects; however, this is largely covered by the annotations.

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 dense but every sentence adds value, front-loaded with the core purpose and output. It covers version, datafile, and debugging alternatives without unnecessary fluff, maintaining a clear structure.

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?

Given the related sibling tools and output schema, the description is complete: it states what the tool does, the exact return fields, how to handle versions and datafiles, and when to delegate to a tracing tool. Nothing essential is missing for an agent to invoke 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?

All 5 parameters are described in the schema (100% coverage), and the description adds crucial extra semantics: version explains 0 default and how to test drafts, datafile explains binding and JSON requirement, slug/workflow_id explains mutual exclusivity. This goes well beyond the schema.

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 purpose: 'Run a workflow now and return the outcome' with a specific list of return fields. It distinguishes itself from sibling tools like get_workflow_run and get_workflow_run_traces by describing the action and pointing to those for per-block detail.

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?

Provides explicit when-to-use guidance: testing an unpublished draft via version=<n>, testing with a datafile without wrapping in an endpoint, and pointing to get_workflow_run_traces for debugging. This covers both when to use and when to use an alternative.

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