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

No annotations are provided, so the description carries the full burden. It states input is 'discarded' but doesn't clarify whether this means the tool rejects the input (validation failure) or ignores it after a check. This ambiguity is significant; an agent might think the tool accepts any input and just notes the charset. The behavior of validation (returning success/failure) is not disclosed.

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 extremely terse ('Bech32 charset, input discarded') but it's under-specified, not concise. It omits crucial detail about validation semantics. It front-loads the purpose but fails to earn its brevity because it leaves critical usage questions unanswered.

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?

With 9 parameters and no annotations or output schema, the description is woefully incomplete. It doesn't explain what the tool does with inputs beyond 'discarded', whether it validates them, what the return value looks like, or why an agent would call this. The complexity of 9 irrelevant-looking parameters (from 'ref' to 'query') suggests a validation tool, but the description doesn't bridge that gap.

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 has 100% coverage with descriptions for all 9 parameters, and the descriptions are clear (e.g., 'Git ref name; discarded after the shape check'). The tool description doesn't add param-specific meaning but doesn't need to since schema is thorough. Baseline 3 is beaten because the parameter descriptions themselves already state the discard behavior, aligning with the tool's purpose.

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 'Bech32 charset, input discarded' indicates the tool validates Bech32 encoding but explicitly says input is discarded/rejected, which is clear about the tool's purpose as a validator. It distinguishes from siblings like validate-json or file-path-ok by naming Bech32 charset specifically, though it doesn't mention checksums or specific validation rules.

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?

There is no explicit when-to-use or when-not-to-use guidance. The description doesn't mention alternatives like validate-json or domain-shape for similar validation tasks. It only implies that input is checked and discarded, but doesn't clarify why an agent would choose this over other validation tools.

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