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

With no annotations provided, the description carries the full burden, and it excels: it discloses that checks are 'plain keyless GET' requests, every 30 minutes, from Cloudflare's network, and even explains the edge-case where HTTP 200 error envelopes are probed by body and reported as failing. It also states the output shape for both the summary and detail modes.

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 dense but each clause earns its place: scope, methodology, edge-case behavior, two invocation modes, and practical usage guidance are all packed into a few sentences. Key information is front-loaded, and there is no filler or repetition.

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?

Even without an output schema, the description compensates by listing what the summary and per-service detail contain — up/down counts, failing services, latest check, last_success_at, down_since, uptime, note, and recent check history. Combined with the explicit use-before-testing guidance, an agent has enough to select and call the tool correctly.

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 input schema already describes the single service parameter as an optional id/name/hostname substring and explicitly says to omit for the summary; schema coverage is 100%. The tool description largely repeats that information rather than adding new parameter-level meaning, 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?

The description opens by naming the exact resource ('~39 public mock/testing APIs') and the operation ('live status... checked'), with a concrete list of example APIs. This makes it immediately distinguishable from siblings like add_resource, query_records, and write_records, which are project/data operations.

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 explicitly states the trigger: 'Use it before pointing tests or tutorials at a public API.' It also explains the two modes — no argument for the summary, or pass a service for single-service detail — so an agent knows exactly when and how to invoke it.

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