Check that earlier constraints (numbers, dates, codes, quoted terms, negations) survive into a later plan or summary

$0.005 USDC per call · Agent infrastructure · POST /api/v1/constraint-carryover · Id constraint-carryover

Takes the constraints an agent was given (budget caps, deadlines, identifiers, prohibitions) and a later artifact (plan, summary, handoff, tool arguments) and reports for each constraint whether its concrete atoms still appear: numbers with their unit or currency, ISO dates, codes, quoted terms, or caller-listed anchor strings, with offsets. For a negated constraint it also reports whether the closest matching sentence still carries a negation cue. Rule-based: it checks that the specifics survived, not that the artifact obeys them, and a constraint with no extractable atoms returns unknown rather than carried.

What you get

Detects silently dropped constraints at every handoff between steps. 50 constraints per $0.005 call.

Call it

Send the JSON body below to https://agents.writerslogic.com/api/v1/constraint-carryover. An unpaid request answers 402 with the price and how to pay; a request that fails with a 5xx status is not charged.

curl -i -X POST https://agents.writerslogic.com/api/v1/constraint-carryover \
  -H 'content-type: application/json' \
  -d '{"constraints":[{"id":"c1","text":"Total spend must not exceed $5,000 before 2026-12-31."},{"id":"c2","text":"Do not contact the customer by phone."}],"target":"Plan: book venues with a $5,000 cap, all invoices settled by 2026-12-31. Contact the customer by email only."}'

Input

Field	Type	Required	Description
`constraints`	array<object>; max 50 items	yes	Up to 50; 20000 characters of constraint text in total.
`target`	string; length 1..60000	yes	The later artifact that must still honor the constraints.

Example request body

{
  "constraints": [
    {
      "id": "c1",
      "text": "Total spend must not exceed $5,000 before 2026-12-31."
    },
    {
      "id": "c2",
      "text": "Do not contact the customer by phone."
    }
  ],
  "target": "Plan: book venues with a $5,000 cap, all invoices settled by 2026-12-31. Contact the customer by email only."
}

Result

The response is { "data": ..., "_provenance": ... }. data carries these fields; _provenance is a signed W3C Verifiable Credential with a C2PA-style manifest, checked free at POST /api/v1/verify-provenance.

Field	Type	Required	Description
`status`	string; one of "pass", "fail", "unknown", "unsupported"	no	pass: every rule held. fail: a rule was violated (see witnesses). unknown: the input lacks the evidence to decide. unsupported: outside what this engine covers. Missing evidence is never a pass.
`constraints`	array<object>; max 50 items	no
`witnesses`	array<object>	no
`versions`	object	no	Every semantic dependency of this answer (engine, tables and their as-of dates, tokenizer, calendar, rounding profile).
`limits`	array<string>	no
`deterministic`	boolean	no	Always true: pure code, no model.

Pay and connect

Available through: x402 (USDC on Base), MCP. MCP clients reach it through the context-evidence-kit package.

Machine-readable

This agent as JSON (schemas, example, OpenAPI operation)
Free signed sample response
OpenAPI 3.1 · Catalog · Index of every agent