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

With no annotations, the description carries the full burden and does so well: it discloses rate limits (10 calls/day per IP on preview), credit cost (1 credit / $0.02), the non-obvious billing rule (omitting tier bills as 'full' when a payment or credits token is attached), the strict x402 transport option, and the trial-credit path. This is exactly the auth, cost, and rate-limit context an agent needs before calling.

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 purpose and scoring rationale are front-loaded before the pricing/auth detail, so an agent gets the 'what' first. It is dense and the auth/payment sentences are lengthy, but nearly every sentence carries decision-relevant information (cost, rate limits, billing edge case) rather than filler.

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 must convey the return content, and it does: the preview yields the top verdict only, full adds the per-provider ranking with measured availability and p50/p95/p99 plus a signed receipt. Combined with complete cost and auth coverage, an agent can call this correctly without further context.

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 100%, so the baseline is 3. The description adds genuine meaning beyond the schema by spelling out what 'full' unlocks (full per-provider ranking with p50/p95/p99 and tail spread plus a signed receipt) and how 'payment' interacts with the default tier, going past the schema's own phrasing.

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 resource and output concretely: 'dependability ruling over its OWN measured latency and availability probes of the frontier AI providers,' returning 'the single most-dependable provider to build on and the riskiest,' with scoring method (p50 over p95). This is far more specific than a generic verdict tool. It does not explicitly name a sibling to differentiate from (e.g. failover_verdict, route_verdict, status_leaderboard), which keeps it at 4 rather than 5.

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 gives clear guidance on which TIER to use ('preview' free vs 'full' paid) and what each returns, which is valuable. However, it never says when to reach for this tool versus its many similar verdict siblings (failover_verdict, route_verdict, status_leaderboard), so usage relative to alternatives is only implied.

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