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

With no annotations, the description carries the full burden, and it does meaningful work: it discloses that the response covers not only what is checked but explicitly 'what is NOT assessed', and that the call costs nothing. It doesn't state the return format explicitly, but the content categories are well enumerated for a zero-parameter read.

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?

A single front-loaded sentence that packs scope, return contents, and cost with no filler. Every clause earns its place.

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, so the description must convey what comes back, and it lists the returned information categories capably. For a no-parameter, no-annotation listing tool this is close to sufficient; only an explicit 'call this first' routing hint is missing.

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?

There are zero parameters, so the schema imposes no documentation burden and the baseline of 4 applies. The description adds no parameter detail because none exists to explain.

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 ('List') and resource ('the architecture checks the Sanity Check runs') plus the exact contents returned (families, plain-language descriptions, gaps, pricing, credits). It is clearly a discovery/catalogue tool, distinct from the action-oriented siblings (run, sample), though the mention of 'how run credits work' slightly overlaps the territory of sanity_check_credit_status.

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?

'Free.' implies this is the cheap first step before spending credits, but the description never explicitly says 'call this before sanity_check_run' or names siblings as alternatives. Usage is inferable rather than stated.

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