validate_llpin

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

Annotations already declare readOnlyHint and idempotentHint, covering the safety profile. The description adds that the tool 'Returns validation result with decoded segments,' which is meaningful behavioral information, but it does not discuss edge cases, error patterns, or any other behavioral nuance beyond that.

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 compact and front-loaded: a short purpose line, a use-case line, and a minimal Args/Returns breakdown. There is no filler or redundant background, though the Args block does overlap with the schema.

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 simple single-parameter, read-only validation tool with an output schema present, this description covers the essential points: what it validates, when to use it, and that the result includes decoded segments. It just misses minor edge-case and format-variant detail, but the output schema and annotations fill most remaining gaps.

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 description coverage is 100%, so the schema already fully documents the llpin parameter. The description's Args line merely repeats 'LLPIN in format AAA-XXXX' but omits the additional accepted variant 'AAAXXXX' that the schema explicitly permits, which is a narrowing that could mislead an agent rather than adding value.

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 with 'Validate LLPIN (Limited Liability Partnership Identification Number)', a specific verb and resource. The 'Use when verifying LLP registration numbers' line further clarifies the target, distinguishing it from the many sibling validation tools.

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 explicit instruction 'Use when verifying LLP registration numbers' gives a clear when-to-use context. It does not enumerate alternatives or explicit when-not-to-use conditions, but given the sibling context of separate validators for other document types, the intended use is clear.

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