list_failing_tests

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

No annotations are provided, so the description carries the full burden. It discloses the scope and the kind of output, but it does not mention that this is a read-only operation, what happens if no run exists or no tests fail, or any permissions/dependencies. Since an output schema exists, the description's enumeration of return fields is partly redundant, but the 'generic vs hand-written' distinction adds useful semantic context.

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 concise and well-structured: the first sentence states the primary purpose, and the second elaborates on the output. It is front-loaded with the core action and contains no filler or redundant wording.

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, zero-parameter tool with an output schema, the description is complete enough. It captures the essential purpose, scope, and distinguishing return information. No key context appears missing.

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 empty schema has 100% coverage. According to rubric, 0 params gives a baseline of 4. The description does not need to explain parameters, and it doesn't introduce confusion.

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 ('List') and resource ('failing tests') with clear scope ('in the last dbt run'). It also enumerates returned fields (test name, model/column, rows failed, generic vs hand-written), making it unambiguous and distinct from siblings like sample_failing_rows and run_summary.

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 context for when this tool applies ('last dbt run' and listing all failures), but it does not explicitly mention alternatives or scenarios where a sibling tool like sample_failing_rows would be preferable. Thus it has clear context but no exclusions.

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