Anthropic's Claude for Legal gives lawyers the AI workflow — drafting, redlining, deal diligence, docket monitoring, regulatory tracking. Verdict makes that work product defensible. Every Claude legal output becomes a Sealed Evidence Record (SER v0.1) with payload hash, Merkle root, attorney review state, citations, and a court-preparable custodian packet.

This package is the stdio MCP server. For the remote MCP server (OAuth, retention, HSM signing, Rekor anchoring), point Claude Cowork at https://verdict.systems/api/mcp.

Why this exists

Claude for Legal shipped May 12, 2026 with 12 practice-area plugins, 80+ specialist agents, and 20+ MCP connectors (Slack, Google Drive, CoCounsel Legal, Box, Ironclad, DocuSign, iManage, Everlaw, CourtListener, Trellis, Aurora, Definely, Solve, TopCounsel, Linear, Jira, Asana, Lawve, Courtroom5, Descrybe). The suite includes guardrails for accuracy (source attribution, citation verification, conservative privilege defaults).

But it does not include a forensic evidence layer:

• No cryptographic content sealing
• No chain-of-custody record
• No FRE 902(14) authentication packet
• No transparency-log anchoring

State bar opinions (Texas Op. 705, Florida Op. 24-1, et al.) and proposed Federal Rule of Evidence 707 are converging on a single requirement: an attorney who relies on AI output must be able to authenticate exactly what the model produced, what was reviewed, and what was approved. Verdict is that record.

Install

Claude Code

claude mcp add verdict -- npx -y @verdict-systems/mcp

Claude Cowork / claude.ai

Add the remote endpoint via Settings → Connectors:

https://verdict.systems/api/mcp

Manual .mcp.json

{
  "mcpServers": {
    "verdict": {
      "command": "npx",
      "args": ["-y", "@verdict-systems/mcp"]
    }
  }
}

Verify

verdict-mcp --version
verdict-mcp --help

The three tools

| Tool | Purpose | |---|---| | verdict_create_evidence_record | Deterministically seals a Claude legal AI output as a Sealed Evidence Record (SHA-256 payload hash + Merkle root + chain of custody + attorney review state + citations + risk flags). | | verdict_score_evidence_readiness | Scores 0–100 whether an output has enough provenance for audit, discovery, outside-counsel-guideline review, or FRE 902(14) authentication. Returns court_packet_ready / outside_counsel_guideline_ready / audit_gap_review_required / not_defensible. | | verdict_export_fre902_certificate | Drafts a custodian certification packet from a sealed record. Output is a preparation aid for counsel — qualified custodian must sign before any filing. |

All three tools are read-only and non-destructive (readOnlyHint: true, destructiveHint: false).

Example: seal a contract review

> Review this NDA against our playbook. Then seal the review with Verdict.

Claude calls verdict_create_evidence_record with the matter id, workflow contract_review, summaries, model version, citations, and review disposition. The tool returns:

{
  "evidence_record_id": "ser_b9f2e0a4c1d8e3a7c0f1",
  "schema": "ser.v0.1.legal_ai_output",
  "payload_hash": "b9f2e0a4...",
  "merkle_root": "82dc11ef...",
  "chain_of_custody": {
    "sequence": 1,
    "prior_root": null,
    "signer": "sandbox.verdict.systems",
    "transparency_anchor": null,
    "retention_class": "sandbox_30_day"
  },
  "legal_review": {
    "human_review_status": "pending",
    "attorney_reviewer": null,
    "citations": ["Vendor Playbook v3.4", "MSA-2024-018"],
    "risk_flags": ["mutual_indemnity_deviation"]
  }
}

Data hygiene

• Send summaries and hashes — not privileged source text. The sandbox is for provenance metadata, not document content.
• For full document custody, retention policy, HSM-bound Ed25519 signer identity, and Sigstore Rekor transparency-log anchoring → contact [email protected] for a tenant.

Sandbox vs production

| Capability | Sandbox (this package) | Production tenant | |---|---|---| | Deterministic SER schema | ✓ | ✓ | | SHA-256 payload hash | ✓ | ✓ | | Merkle rooting | ✓ | ✓ | | Chain-of-custody scaffold | ✓ | ✓ | | OAuth tenant isolation | — | ✓ | | Retention policy enforcement | — | ✓ | | HSM-bound Ed25519 signing | — | ✓ | | Sigstore Rekor anchoring | — | ✓ | | Matter-scoped access controls | — | ✓ | | FRE 902(14) signed cert (live) | draft only | ✓ |

License

Apache 2.0. See LICENSE.

Security

If you discover a vulnerability, please email [email protected]. See https://verdict.systems/.well-known/security.txt for the full security policy.

Links

• Verdict / Claude for Legal strategy
• Install instructions
• SER v0.1 specification
• Evidence-readiness benchmark