List Scenario Runs

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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds value beyond that: it discloses that the tool depends on an active project context, and that the return shape changes depending on which parameter mode is used (pass/fail counts per run vs per-step results). No contradiction with 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?

Three short sentences, roughly 45 words, with the core purpose front-loaded. The alternate mode and the project-context prerequisite each earn their place, and there is zero redundancy or filler.

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 4-parameter list tool with readOnlyHint=true and full schema coverage, the description covers the main operating modes, the return shape difference, and the project-context prerequisite. The absence of an output schema means the exact run object shape is undocumented, but the description gives enough for an agent to call and interpret the result 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 100%, so the baseline is 3. The description earns a 4 by adding cross-parameter semantics the schema can't express: the conditional exclusivity between runId and scenarioId, and the behavioral consequence of choosing runId (returns per-step results). This gives the agent decision logic, not just field definitions.

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 opens with a specific verb and resource — 'List the runs of a scenario with pass/fail counts per run' — and immediately clarifies what each call mode returns (aggregate pass/fail counts vs per-step results for a single run). This distinguishes the tool's two behaviors internally and separates it from siblings like list_scenarios or get_test_run by making the resource and result shape explicit.

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 gives clear invocation guidance: it tells the agent when to pass runId versus scenarioId ('Pass runId to get one run with its per-step results instead — scenarioId is then not needed') and states the prerequisite that project context must be set. It stops short of naming sibling tools or explicit when-not-to-use conditions, so it doesn't earn a 5.

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