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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description nonetheless adds substantial behavioral context by disclosing what the comparison returns: common ancestor, the diverging path segments (with meanings), shared field axes, and which aspects differ. It stops short of describing format/pagination, but for a read-only tool that's minor.

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?

It is a single sentence but heavily nested with an em-dash and parenthetical example, making it hard to parse. The core intent is front-loaded, but the structure could be tightened considerably.

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 usefully compensates by enumerating the comparison's components. Combined with the read-only annotations and full schema coverage, an agent has enough to call it correctly, though missing usage guidance and return-format details keep it from perfect.

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 both convention-name parameters and the api_token auth note are fully documented in the schema. The description adds no extra meaning about the parameters, so the baseline of 3 applies.

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 clearly states this relates two conventions, distinguishing it from single-convention siblings like get_convention and list_conventions. The purpose is understandable, though the phrasing is output-oriented (describing what's returned) rather than a clean verb+resource statement like 'compare two conventions'.

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 guidance on when to use this versus get_convention or list_conventions, nor any stated preconditions. Usage is only weakly implied by the 'two conventions' framing, with no alternatives or exclusions named.

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