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

With no annotations at all, the description carries the full burden and does well: it discloses the return shape ('paths and errors') and rules out side effects ('no network access or storage'), telling the agent this is a pure computation. It stops short of saying whether failures throw or are returned as structured errors, but the core behavioral profile is present.

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?

Three short sentences with zero filler; the enumerated capability list is front-loaded and the exclusion clause is placed last where it reads as a boundary rather than a caveat up front. Nothing could be cut without losing information.

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?

For a two-parameter, side-effect-free validator with no annotations and no output schema, the definition covers purpose, scope, return shape, and side-effect profile. Only the error-reporting format and any limits on schema size or nesting depth remain unaddressed.

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, and the description earns a bump by enumerating exactly which JSON Schema keywords are honored — information the schema parameter text only gestures at with 'Limited JSON Schema subset.' That enumeration directly tells the agent what to expect from the 'schema' argument.

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 ('Check') and resource ('supplied tool arguments') and immediately bounds the scope to a named subset of JSON Schema keywords (type, required, properties, additionalProperties, enum, const, bounds, arrays). An agent can tell this apart from diagnose_tool_failure or ecosystem_catalog 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 trailing 'NOT full JSON Schema validation' is a useful capability boundary, but it is a scope caveat rather than selection guidance. There is no explicit statement of when to reach for this tool versus a sibling, so the agent must infer that it is a pre-flight check before invoking a tool.

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