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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds genuine behavioral context by disclosing the data-source fallback (trace data when available, otherwise transcript-based diagnosis), which affects reliability and completeness of results.

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 tight sentences, front-loaded with the core purpose and followed by outputs and availability caveat. No filler or redundant restatement of the title.

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?

With no output schema, the description usefully summarizes what the diagnosis returns and notes the data-source fallback, which is enough for an agent to call it correctly. The only gap is the absence of guidance against related diagnosis/insight siblings.

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 both parameters (customerId superadmin note and conversationId) are fully documented in the schema. The description adds no additional parameter meaning beyond what the schema provides, so 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?

The description states a specific verb and resource ('get step-level failure diagnosis for a run') and enumerates the concrete outputs (first failed step, cascade effects, root cause, per-turn timeline). It implicitly differentiates from the sibling get_step_failure_aggregation by being per-run and diagnostic rather than aggregate, but never names that sibling explicitly.

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?

It states availability ('Available for all runs') and a fallback mode, which implies usage context, but gives no explicit when-to-use vs. alternatives despite close siblings like get_step_failure_aggregation, get_run_insights, and get_run. The agent must infer which diagnosis tool to pick.

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