invariance_workflow_observability_list

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

Annotations already declare readOnlyHint=true and openWorldHint=true, covering safety and open-world semantics. The description adds detail on the rollup contents (counts, evidence mix, cost/token totals), which is useful but does not go into pagination, ordering, or whether the list is exhaustive across all workflows. Given the annotations lower the bar, this is adequate but not rich – a score of 3 is appropriate.

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 a single, well-structured sentence that front-loads the core purpose ('List workflow observability rollups') and then enumerates the content scope. Every word adds value, with no redundancy or filler. It is appropriately sized for the tool's complexity.

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?

Despite having no output schema, the description tells the agent exactly what fields each rollup includes (counts, evidence mix, cost & token totals), which is sufficient to set expectations. It does not mention pagination or sorting, but for a list tool without parameters, this is not critical. The presence of a sibling 'get' tool implies the list is a high-level overview, and the description covers the essentials.

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 tool has zero parameters, so the schema coverage is trivially 100%. There is nothing for the description to explain about parameters. Per the rubric, a baseline of 4 applies for 0-parameter tools, and the description appropriately avoids inventing parameter details. It does not add parameter semantics because none exist.

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 verb 'List' and resource 'workflow observability rollups', then specifies the exact content of each rollup (per workflow_key: execution/open/closed counts, evidence mix, cost & token totals). This differentiates it from siblings like invariance_workflow_observability_get (which retrieves a single rollup) and invariance_workflow_observability_executions (which lists executions), leaving no ambiguity about what the tool returns.

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 implies usage: it's the list operation for workflow observability rollups, contrasting with the 'get' sibling. However, it does not explicitly state when to prefer this over alternatives or mention exclusions. The context is clear enough that an agent can infer its role among siblings, so it earns a 4 rather than a 5.

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