Compare JSON structures and return bounded changes at JSON Pointer paths. FREE during validation. No key, credits or wallet. Existing source and input limits apply.
| Name | Required | Description | Default |
|---|---|---|---|
| input | Yes | ||
| requestId | No | Optional legacy field; ignored in free mode. | |
| maxPriceMicroUsd | No | Optional legacy field; ignored in free mode. |
| Name | Required | Description | Default |
|---|---|---|---|
| equal | Yes | ||
| scope | Yes | ||
| changes | Yes | ||
| truncated | Yes |
Changes observed during successful MCP inspections.
Input schema / properties / maxPriceMicroUsd / descriptionPrevious value: -"Explicit maximum new debit; 0 means recovery only."New value: +"Optional legacy field; ignored in free mode."Input schema / properties / maxPriceMicroUsd / maximumRemoved value: -999999999999Input schema / properties / requestId / descriptionPrevious value: -"Persist the ID returned by agent_utilities_prepare. Reuse after uncertainty."New value: +"Optional legacy field; ignored in free mode."Input schema / properties / requestId / patternRemoved value: -"^\\d{13}_[A-Za-z0-9_-]{16,80}$"Input schema / requiredPrevious value: -[
- "input",
- "requestId",
- "maxPriceMicroUsd"
-]New value: +[
+ "input"
+]Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, openWorldHint, idempotentHint and destructiveHint, lowering the bar. The description still adds useful context, noting results are 'bounded', that it is free with no key/credits/wallet, and that source and input limits apply, which the structured fields do not convey.
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 short sentences with the core purpose front-loaded and zero filler. The free-mode sentence is slightly promotional but still informative about auth/cost, so it earns most of its place.
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?
An output schema exists, so return values need not be explained. Given the nested input and read-only annotations, the description covers the essentials (comparison, bounded output, free/no-key operation, limits) without leaving a critical gap.
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 67%; the two legacy fields are documented in the schema and the before/after pair is self-evident. The description's 'bounded changes' loosely maps to maxChanges and 'JSON Pointer paths' to the output, but it adds little concrete parameter meaning, 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?
States a specific verb (compare) and resource (JSON structures) and even describes the return (bounded changes at JSON Pointer paths), which clearly distinguishes it from sibling tools like data_json_patch and data_json_canonical. It stops short of explicitly naming which JSON sibling to prefer, so it is clear but not sibling-routing.
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 guidance on when to use this tool versus alternatives such as data_json_patch, data_json_pointer, or contracts_openapi_diff. The 'FREE during validation' note is pricing context, not a usage condition, so an agent gets no when/when-not signal.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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