# Api Contracts — Record Sequence Diff

> Api Contracts — Record Sequence Diff is a paid API for AI agents from www.mahastrategies.com, paid per call via x402, $0.035092/call, status unknown (last checked 2026-10-23).

Compares two ordered lists of pinned HTTP contract projections to identify insertions, deletions, and reorderings of shared records, treating insertions distinctly from reorderings.

## Facts

- Endpoint: POST https://www.mahastrategies.com/api/v1/verify/api-contracts/record-sequence-diff?utm_source=zero.xyz
- Price: $0.035092/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-23
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-contracts-record-sequence-diff-3d891d5c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_OAI4s8zkjoPAX-Z9nJGwh

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability api-contracts-record-sequence-diff-3d891d5c -d '<json body>'
```

Example prompt: Compare these two lists of public API contract projections and tell me which shared records changed order, which were inserted, and which were deleted — make sure insertions aren't counted as reorderings.

## When to prefer this

Choose this endpoint when you need to compare two ordered sequences of HTTP contract projections and need the diff to correctly distinguish genuine reorderings of shared records from new insertions — especially important when naive diff tools would misclassify insertions as shifts. It operates offline on typed nonpersonal metadata only (public or synthetic data classes), making it suitable for CI pipelines and governance workflows that do not require live transport execution or schema resolution.

## Known failure modes

- Input arrays exceeding 32 items will be rejected
- dataClass must be 'public' or 'synthetic'; other values cause validation errors
- nonpersonalMetadata must be explicitly set to true or the request is rejected
- Malformed or non-array inputs for before/after will fail schema validation
- Result unavailable after 24-hour retention window

## How this service works

Compare pinned HTTP contract projections and shared-record order without treating insertion as reordering. No transport execution, schema resolution or compatibility certificate. Offline typed nonpersonal metadata only. Result retention: 24 hours; minimal receipt metadata: 90 days.

## Output

A structured diff of the two input contract projection sequences, indicating which records are shared and whether they changed relative order (reordering), which records appear only in the after list (insertions), and which appear only in the before list (deletions). Results are available for 24 hours; minimal receipt metadata is retained for 90 days.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "after": {
   "type": "array",
   "maxItems": 32,
   "minItems": 0
  },
  "before": {
   "type": "array",
   "maxItems": 32,
   "minItems": 0
  },
  "dataClass": {
   "enum": [
    "public",
    "synthetic"
   ],
   "type": "string"
  },
  "nonpersonalMetadata": {
   "type": "boolean",
   "const": true
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-contracts-record-sequence-diff-3d891d5c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from www.mahastrategies.com](https://www.zero.xyz/host/www.mahastrategies.com/llms.txt)