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

Annotations already establish readOnly/closed-world/safe, so the description's job is to add behavior, which it does: a built-in list of ~17 actions, suggestion of the most-used label as standard, and the specific lint categories. The 'context-dependent groups' caveat is genuinely useful behavioral context. It stops short of describing output shape.

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?

Purpose is front-loaded and every sentence carries information (action list, standard suggestion, flag types, merge caveat). It is a single dense paragraph with some run-on stacking, which keeps it from a 5.

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 no output schema, the description does cover the analytical behavior and inputs adequately. It leaves the return format implicit, but the flag categories and 'suggests the most-used label as the standard' make the expected output inferable.

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 baseline would be 3, but the description adds real meaning the schema lacks: that repetitions matter for count correctness, and that groups are user-supplied synonym sets merged conservatively. That is beyond the schema's terse 'Labels, one per line, repeated per occurrence'.

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 first sentence states a specific verb and resource ('Check a list of interface labels for consistency') and the rest enumerates exactly what kinds of inconsistency are detected: synonym grouping, most-used standard, mixed case, all caps, punctuation, generics. It is clearly distinct from siblings like label_clarity_check or repeated_label_check.

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?

It gives concrete input guidance ('one per line; repeat a label once per place it appears so counts are real') and an important caveat: 'Some groups depend on context; merge only where the action is truly the same.' It does not explicitly name when to prefer a sibling tool instead, so 4 rather than 5.

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