device_health

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

Annotations only declare readOnlyHint=true; the description adds genuinely non-obvious behavior: graceful degradation when a driver lacks get_environment (the section degrades to a note) and the presence of a 'healthy' flag plus an 'issues' list. No contradiction with the read-only annotation, though rate limits / cost of aggregation are unaddressed.

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?

Front-loaded with a [READ] tag and the core aggregation scope in the first clause; the degradation note and return-shape sentence each carry information. Slightly verbose in the 'Args:' block format, but no filler sentences.

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?

There is no output schema, so the description usefully names the return contract ('healthy' flag, 'issues' list) and flags partial-failure behavior. Complete enough to call safely; the only gap is guidance on alternative diagnostic tools when issues are reported.

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% and the schema itself says nothing about target beyond string|null. The description compensates well by explaining the value source ('Device name from config') and the default behavior when omitted, which the schema's bare default:null does not convey.

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 concrete composite resource (aggregated health = facts + interface up/down counts + environment) with enough specificity to distinguish it from sibling primitives like device_facts, get_interfaces and interface_health_rca. An agent can tell this is an umbrella roll-up rather than a raw data getter without opening any schema.

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 implies a 'one-shot health check' use case but never says when to prefer it over device_facts + get_interfaces, nor when to escalate to interface_health_rca or bgp_neighbor_rca for diagnosis. It does give practical arg guidance (omit target to use the configured default), which is context, not a when-to-use rule.

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