backend_health_rca

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

Annotations declare readOnlyHint=true and the description is consistent with a read operation. Beyond that it adds real behavioral detail: injecting 'upstreams' skips the live pull, and outages are classified into named causes (connection refused, L4/L7 health-check failure, DNS, admin maint/drain, all-servers-down) each with a recommended action.

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 core behavior is front-loaded in the first sentence, followed by an Args block and a Returns block. Slightly longer than needed and the return-dict detail is verbose, but every section maps to something an agent needs.

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?

No output schema exists, yet the description documents the return dict (servicesEvaluated, outages, degraded, findings with per-service fields and cause/action, note), and all three parameters are explained. For a three-mode read-only RCA tool this is sufficient.

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 0%, so the description carries the full burden and does: 'service' is an optional filter that only applies when pulling live, 'upstreams' is documented with its row shape {service, server, address, status, checkInfo} and the fact that it bypasses the live pull, and 'target' is a proxy target name from config with a default fallback.

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 (pulls server-level upstream health, groups per service, classifies each outage) and resource, and the opening line names the diagnostic scope. It is clearly distinguishable from siblings like error_rate_rca or upstream_detail.

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?

Explicitly says to pass 'upstreams' for pure analysis versus a target to pull live, and that 'service' filters live pulls only. It gives clear mode-selection guidance but never names a sibling or a when-not-to-use condition relative to the adjacent error_rate_rca tool.

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