aethis_explain_failure

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

Annotations already declare readOnlyHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds real value beyond that by disclosing the return payload — diagnosis, criteria with DSL metadata (waivable, review_required), and a fix hint — which is important since no output schema exists.

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?

Two sentences, front-loaded with the purpose before the usage and return details; every clause carries information. The return-value clause is slightly list-heavy but earns its place given there is no output schema.

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 read-only diagnostic tool with full schema coverage, the description supplies the missing piece — what the diagnosis returns — which compensates for the absent output schema. Only the differentiation from aethis_explain is left unaddressed.

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 description coverage is 100%, so all four parameters (ruleset_id, field_values, expected_outcome, test_name) are already documented in the schema. The description adds no format or syntax detail beyond it, so the baseline 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?

States a specific verb+resource ('Diagnose why a ruleset produced an unexpected outcome') and scopes it to test inputs, which is clear. It does not explicitly distinguish itself from the sibling aethis_explain, so an agent must infer the boundary between 'explain' and 'explain_failure'.

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?

Gives a clear triggering context — 'Use during rule authoring when a test fails' — which tells the agent when this tool is appropriate. It stops short of naming an alternative (e.g. aethis_explain) or stating exclusions, so it is context without routing.

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