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

Annotations already declare readOnly/idempotent/non-destructive, so safety is covered. The description adds real behavioral context beyond that: deterministic output (caller-supplied generated_at), byte-identical parity with the tools/552 browser workbench, and the execution_hash linkage into human hunk/disposition receipts.

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?

Front-loaded with the core action and its outputs; every sentence carries workflow or parity information. The workbench clause is somewhat sprawling but is not idle filler.

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 fully carries the return-value burden: it enumerates hunks, per-hunk digests, algorithm declaration, and the execution_hash used downstream. An agent has everything needed to call it and to chain it correctly.

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 original, revised, and generated_at are already documented. The description reinforces original/revised semantics but adds no format or edge-case detail beyond the schema, which is the expected baseline when the schema does the heavy lifting.

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?

States a specific verb (diffs) and two named resources (original text vs. revised version) and specifies the outputs: line-level hunks plus a diff receipt. It is immediately distinguishable from redline_verify, which it names as the downstream consumer.

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 opening 'An agent proposes an edit' gives the triggering context, and the closing sentence explicitly routes the agent to redline_verify with the bundle. No explicit when-not condition is stated, but the workflow position is unambiguous.

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