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

Beyond the annotations (destructiveHint: true, readOnlyHint: false), the description adds meaningful behavioral context: deletion is permanent, cannot be undone, and also removes stored outputs. It also instructs the agent to follow any llmContext guidance in results, which is an operational behavior not captured by structured 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 two sentences with no filler. It front-loads the core action, states the consequential side effect, and includes a brief agent-relevant instruction about llmContext. Every sentence earns its place.

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 simple 3-parameter destructive tool with a 100% described schema, strong annotations, and an output schema, the description is nearly complete. It covers purpose, scope, permanence, and side effects. The only notable gap is the lack of an explicit alternative comparison with cancel_workflow_run.

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?

The input schema already provides complete descriptions for all three parameters, including the runId source and environment pinning constraints. The description adds no parameter-specific semantics beyond the general statement about stored outputs, so the schema carries the load and the baseline score of 3 applies.

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 uses a specific verb ('delete') and resource ('a workflow run'), and further defines the scope by saying it removes stored outputs specifically for the 'workflows group'. This distinguishes it from sibling delete_*_run tools (classify, extract, split, etc.) without needing to inspect each.

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 clear that this tool applies to workflow runs, but it does not explicitly state when to prefer deletion over cancellation or other operations. Given that cancel_workflow_run exists as a sibling, guidance on 'use cancel if you only need to stop a run' would improve this dimension, but the resource type is clearly implied.

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