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

Annotations declare readOnlyHint=false, idempotentHint=false, openWorldHint=true; the description is consistent (mutation, not read-only) and adds meaningful context: 'Free; preserves original sources' discloses cost and side effects, and 'cannot promise a successful capability result' sets outcome expectations. It still leaves the precise mutation semantics (what gets overwritten on the revision) unspecified.

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 verb and core action, three tight sentences with no filler. The parenthetical repair-scope list is dense and jargon-heavy but still earns its place as scope-defining content.

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?

No output schema exists and the description does not describe the return value or how pass/fail is reported ('cannot promise a successful capability result' hints at ambiguity but does not resolve it). For a non-idempotent, non-read-only mutation tool with three required params, it should clarify what a caller receives back.

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 67%; packId and componentId carry descriptions but revisionId does not. The description adds nothing about parameter formats, relationships, or which revision to pass beyond 'exact current revision'. Baseline 3 is appropriate given the schema does most of the work.

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 (revalidate) plus scope (apply deterministic runtime layout repairs) against an exact revision, and explicitly says what it is not ('not arbitrary SVG artwork editing'). An agent can distinguish it from siblings like revise_ui_pack_png or replace_ui_component_png. However, the repair scope list ('bar fill openings, panel text/slice regions') is domain jargon that is not clarified.

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?

Provides one exclusion ('This is not arbitrary SVG artwork editing') implying when-not, but never names a positive trigger, prerequisite, or an alternative sibling to prefer. Usage is largely left to inference from the description.

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