Skip to content
SHPBL

SHPBL agent evidence series

Canary Evidence Chain

Synthetic-only canary markers plus a payload-free evidence chain proving where they reappeared.

Status
Submitted, awaiting review
Licence
MIT · zero runtime dependencies
Evidence
25 tests · 72 assertions
Install the MIT tool ↗Download the packagePull request #168 ↗Public specification ↗

The problem

Did our synthetic evaluation data reappear somewhere it should not?

You share an evaluation corpus with a vendor, a model provider or an internal team, then want to know whether that data spread beyond where you released it — into a retrieval index, a model context, a support export, a leaked dump. Ordinary logging cannot answer it, and the answer has to survive scrutiny.

What it does

You generate a synthetic dataset inside the package, mint a canary marker bound to one record and one recipient label, hand that marker to exactly one recipient, and later scan text you already control. A reappearance becomes an entry in a payload-free, hash-linked evidence chain that a third party can verify.

How it works

Markers are only ever minted into data this package generated, so no real customer content is ever used as bait. Scans run over text the operator supplies, and evidence records carry digests and declared metadata rather than the matched payload. The policy in force is published by the server itself.

Tool surface

MCP over stdio. Compatible with Claude Code, Claude Desktop and Cursor, or usable directly as a TypeScript library. No API key, account or Tenable product is required.

  • generate_synthetic_dataset

    Generate the synthetic records canaries may be bound to.

  • mint_canary

    Mint a marker bound to one synthetic record and one recipient label.

  • register_honeypot

    Register a location whose access should count as evidence.

  • scan_for_canaries

    Scan operator-supplied text for minted markers.

  • report_access

    Record an observed access or reappearance as chained evidence.

  • export_evidence

    Export the payload-free, hash-linked evidence chain.

  • describe_policy

    Publish the minting, scanning and redaction policy in force.

  • get_stats

    Report counts for minted markers, scans and recorded evidence.

What it deliberately does not do

  • Canaries are minted only into synthetic data this package generates — never into real records.
  • It scans text you supply; it does not crawl, monitor networks or reach out to third parties.
  • A reappearance is evidence of spread, not proof of who leaked it.

Provenance

Where this came from

SHPBL discovered and composed this product from capability intent across its library and CMPSBL, a sister project by the same developer. The implementation was written fresh from its published behaviour specification, cleared an exact-file review of its release surface, and received its own MIT grant over that reviewed file set. The MIT grant covers only the named files in that one repository; it does not relicense SHPBL, CMPSBL, private harvest machinery, harvested bodies or provenance maps.

SHA-256 · 58508068c0f525bac54c550b91bd907f173bab7f42ed232cd6a000a69878a880

Submission does not imply review, approval, certification or endorsement by Tenable. No Exchange listing exists until a maintainer merges it.