# Tool Context — Schema Directionality

> Tool Context — Schema Directionality is a paid API for AI agents from www.mahastrategies.com, paid per call via x402, $0.035067/call, status unknown (last checked 2026-10-28).

Compares closed tool argument-metadata field contracts to detect request-ingestion directionality breaks between two schema snapshots.

## Facts

- Endpoint: POST https://www.mahastrategies.com/api/v1/context/tool-context/schema-directionality?utm_source=zero.xyz
- Price: $0.035067/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-28
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/tool-context-schema-directionality-48249bf9
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ni4_0V4nLDDx_qd1KCDYb

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 tool-context-schema-directionality-48249bf9 -d '<json body>'
```

Example prompt: Compare these two tool argument schema snapshots — the before list has my old field contracts and the after list has the new ones — and tell me if any directionality breaks exist in the request-ingestion flow; the data is public synthetic metadata.

## When to prefer this

Choose this endpoint when you need to specifically detect request-ingestion directionality breaks in closed tool argument-metadata field contracts between two schema versions. It is distinct from general schema diffing or full MCP compatibility certification tools — it focuses narrowly on field-level directionality in the ingestion direction, offline, using only nonpersonal public or synthetic metadata.

## Known failure modes

- Empty or invalid before/after arrays cause validation rejection
- before array missing required minimum of 1 item returns schema error
- dataClass value outside 'public' or 'synthetic' enum rejected
- nonpersonalMetadata not set to true (const) causes request failure
- Arrays exceeding maxItems of 32 are rejected
- Personal or sensitive data outside allowed data classes refused

## How this service works

Compare closed tool argument-metadata field contracts for request-ingestion breaks. No JSON Schema resolution, arbitrary schema execution or full MCP compatibility certification. Offline typed nonpersonal metadata only. Result retention: 24 hours; minimal receipt metadata: 90 days.

## Output

A report identifying directionality breaks in closed tool argument-metadata field contracts between the before and after schema snapshots, highlighting which fields have ingestion-incompatible directional changes. Results are retained 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": 1
  },
  "dataClass": {
   "enum": [
    "public",
    "synthetic"
   ],
   "type": "string"
  },
  "nonpersonalMetadata": {
   "type": "boolean",
   "const": true
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/tool-context-schema-directionality-48249bf9/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)