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io.github.sipyourdrink-ltd/bernstein-mcp

by sipyourdrink-ltd · remote · no sign-in to list tools · v0.2.0 · published by GitHub user sipyourdrink-ltd

Verifies Bernstein run receipts and hash chains; lists the shipped presets and adapters. Read-only.

Changes · 6
CompareRegistry entry

11 tools: 6 change things and 5 only read.

Scanned Oct 21, 2026

3 checks matched something in the tool definitions. No finding is not a safety guarantee. How the checks work.

claude mcp add --transport http bernstein https://mcp.bernstein.run/mcp

Findings

Matches of fixed checks, with the text they matched.

3 info
  • Infoverify_delegation_chain

    The description mentions "credential".

    Matched text

    description: "...bound, the link's digest algorithm, the credential (registered, issuer = parent subject, h..."

    What this check looks for
  • Infoverify_delegation_chain

    The input schema at properties.context.properties.now.description mentions "credential".

    Matched text

    inputSchema.properties.context.properties.now.description: "Carried for completeness; credential windows are judged at each hop's own ia..."

    What this check looks for
  • Infoverify_delegation_chain

    The input schema at properties.context.properties.credentials.description mentions "credential".

    Matched text

    inputSchema.properties.context.properties.credentials.description: "...e, not_after}. Default {} → every hop's credential is unknown."

    What this check looks for

Tools

Open a tool for its reasons and full description. Descriptions are the publisher's own words, shown as they are.

11 tools

Changes things 6Claude Code: ask
  • server_infoIdentity, version, and request limits for this MCP server.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Identity, version, and request limits for this MCP server.
  • verify_agent_manifestAgent Manifest v0.2 conformance checks on one manifest, stateless, no account: schema (vendored agent-manifest.schema.json), profile context, version, canonicalization, COSE envelo…No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Agent Manifest v0.2 conformance checks on one manifest, stateless, no account: schema (vendored agent-manifest.schema.json), profile context, version, canonicalization, COSE envelope signature (Ed25519, key identified by kid in the protected header; ML-DSA-65 is reported unverifiable). Optionally checks that a TRACE Trust Record cites this manifest by digest. Nothing is fetched; resolvers are checked as URIs only. The manifest hash is sha256 over the COSE payload bytes (or RFC 8785 canonical JSON for object input).
  • verify_chainWalk bernstein chain rows and recompute every link: journal rows (event_hash), lineage spine entries (entry_hash) or audit events (prev_hmac linkage).No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Walk bernstein chain rows and recompute every link: journal rows (event_hash), lineage spine entries (entry_hash) or audit events (prev_hmac linkage). The row kind is detected from the fields, or pass `kind` explicitly. Reports the first divergent index. Pass `entries` as the file text (a JSON array or one row per line, as journal.jsonl is written) for byte-exact hashing; a parsed array also works, but then a float spelled 1.0 or -0.0 in the file cannot be told apart from an integer.
  • verify_delegation_chainTRACE v0.2 delegation-chain conformance, stateless, no account: index every Trust Record by the RFC 8785 digest of its complete form, start at the leaf, follow delegation.parent_re…3 findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.

    Findings

    • Info

      The description mentions "credential".

      Matched text

      description: "...bound, the link's digest algorithm, the credential (registered, issuer = parent subject, h..."

      What this check looks for
    • Info

      The input schema at properties.context.properties.now.description mentions "credential".

      Matched text

      inputSchema.properties.context.properties.now.description: "Carried for completeness; credential windows are judged at each hop's own ia..."

      What this check looks for
    • Info

      The input schema at properties.context.properties.credentials.description mentions "credential".

      Matched text

      inputSchema.properties.context.properties.credentials.description: "...e, not_after}. Default {} → every hop's credential is unknown."

      What this check looks for
    Description, as the server wrote it
    TRACE v0.2 delegation-chain conformance, stateless, no account: index every Trust Record by the RFC 8785 digest of its complete form, start at the leaf, follow delegation.parent_record_hash to the root, and check each hop's signature, the root key against `trusted_root_keys`, the depth bound, the link's digest algorithm, the credential (registered, issuer = parent subject, holder = record subject, window at the hop's own iat) and data_class narrowing under `data_class_lattice`. Classification: provenance-invalid outranks authorization-invalid; an unread link is unverifiable, not broken. Pass `records` as a JSON array or as file text (one record per line or a JSON array).
  • verify_receiptRecompute every hash chain a bernstein run receipt embeds (journal, lineage spine, optional audit range), rebuild the signed subject from the recomputed heads, and check the Ed2551…No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Recompute every hash chain a bernstein run receipt embeds (journal, lineage spine, optional audit range), rebuild the signed subject from the recomputed heads, and check the Ed25519 signature with the key the receipt carries. Needs no secret and reads nothing but the receipt. Returns the verdict, the first failing check, one line per check, and the same verdict as a DSSE envelope signed by this verifier's Ed25519 key (public key at keys_url) so the outcome can be kept and re-checked offline.
  • verify_trace_recordTRACE v0.2 conformance checks on one Trust Record, stateless, no account: schema (vendored trace-claim.json), profile, subject URI, software-only runtime rule, policy digest, publi…No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    TRACE v0.2 conformance checks on one Trust Record, stateless, no account: schema (vendored trace-claim.json), profile, subject URI, software-only runtime rule, policy digest, public-only confirmation key, the embedded signature (EdDSA, ES256 or ES384 with the key in cnf.jwk), appraisal, delegation link shape and references. Nothing is fetched: resolvers are checked as URIs only. `record_sha256` is the RFC 8785 digest of the complete record, signature included — the value a child hop puts in delegation.parent_record_hash.
Only reads 5Claude Code: allow
  • explain_receiptVerify a run receipt and narrate the result in plain language: what the run recorded, which chains recomputed, where the first divergence is, and what an auditor can and cannot con…No findings

    Why it is in this group

    • The name "explain_receipt" says "explain": a word for reading.
    Description, as the server wrote it
    Verify a run receipt and narrate the result in plain language: what the run recorded, which chains recomputed, where the first divergence is, and what an auditor can and cannot conclude without the producing install's keys.
  • explain_trace_mappingHow a bernstein run maps onto a TRACE v0.2 Trust Record: one row per claim with the journal field it is sourced from and the rule that derives it.No findings

    Why it is in this group

    • The name "explain_trace_mapping" says "explain": a word for reading.
    Description, as the server wrote it
    How a bernstein run maps onto a TRACE v0.2 Trust Record: one row per claim with the journal field it is sourced from and the rule that derives it. Pass a run receipt to fill in the rows its embedded journal can answer (subject, iat, model, data_class, policy digest, tool transcript) alongside the receipt's own verdict.
  • get_presetEvery field of one compliance preset as bernstein v3.19.2 resolves it.No findings

    Why it is in this group

    • The name "get_preset" says "get": a word for reading.
    Description, as the server wrote it
    Every field of one compliance preset as bernstein v3.19.2 resolves it.
  • list_adaptersThe agent adapters bundled with bernstein v3.19.2: adapter name, the binary it drives, the module that implements it.No findings

    Why it is in this group

    • The name "list_adapters" says "list": a word for reading.
    Description, as the server wrote it
    The agent adapters bundled with bernstein v3.19.2: adapter name, the binary it drives, the module that implements it.
  • list_presetsThe compliance presets bernstein v3.19.2 ships, with the switches each one turns on.No findings

    Why it is in this group

    • The name "list_presets" says "list": a word for reading.
    Description, as the server wrote it
    The compliance presets bernstein v3.19.2 ships, with the switches each one turns on.

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Install

Pinned to version 0.2.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http bernstein https://mcp.bernstein.run/mcp

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json
{
  "permissions": {
    "allow": [
      "mcp__bernstein__explain_receipt",
      "mcp__bernstein__explain_trace_mapping",
      "mcp__bernstein__list_presets",
      "mcp__bernstein__get_preset",
      "mcp__bernstein__list_adapters"
    ],
    "ask": [
      "mcp__bernstein__server_info",
      "mcp__bernstein__verify_receipt",
      "mcp__bernstein__verify_chain",
      "mcp__bernstein__verify_trace_record",
      "mcp__bernstein__verify_agent_manifest",
      "mcp__bernstein__verify_delegation_chain"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. It assumes the server is installed as bernstein. Review it before you use it.