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

Annotations already establish read-only, closed-world, non-destructive, non-idempotent behavior. The description adds a useful semantic caveat — NOT_DATED means there was nothing to date, not that nothing changed — which prevents a real misreading, but it says nothing about cost, latency, or what the diff output looks like.

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 sentences, with the core operation front-loaded before the caveats. The jargon density costs a little clarity, but nothing reads as padding.

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 read-only three-parameter analysis tool with no output schema, the description covers the intent, the comparison semantics, and one key result-interpretation gotcha. It could say more about what the diff returns, but an agent can call it correctly from this.

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%, with dateA and dateB already labeled as the 'before' and 'after' legal dates. The description reinforces the two-date comparison but adds no format, ordering, or constraint detail beyond the schema, so baseline 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 states a concrete resource and operation: what changed in an act between two legal dates, covering edition state, norm dating, and a semantic diff between D1 projections. It is specific, though internal jargon ('axe O-2', 'projections D1') will not land for an agent without domain vocabulary.

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 routes the agent to law_ask with legalTime when the need is the outcome of a particular question at a date, which is a genuine alternative. But there is no explicit statement of when to use this tool versus law_inspect, law_query, or law_rules, so the boundary of 'edition axis' work is left to inference.

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