sanctions-screening-mcp-server

<div align="center"> <h1>@cyanheads/sanctions-screening-mcp-server</h1> <p><b>Screen names against the consolidated OFAC, EU, UK, and UN sanctions lists and resolve legal entities against GLEIF, fuzzy-matched offline over a local SQLite + FTS5 mirror. A screening aid, not a compliance determination.</b> <div>6 Tools • 3 Resources • 1 Prompt</div> </p> </div>

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Public Hosted Server: https://sanctions-screening.caseyjhand.com/mcp

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[!IMPORTANT] This is a screening aid, not legal or compliance certification. Every tool returns potential matches with a transparent score and source provenance — never a verdict. A hit means "review this candidate against the official source"; an empty result never means "cleared." Real sanctions compliance is a legal process — it requires human review and a qualified compliance determination. This server feeds that process; it does not perform it, and its output is not a compliance record.

Overview

sanctions-screening-mcp-server turns the world's open sanctions data plus the global legal-entity registry into one screening-and-resolution workflow, answered offline and fuzzy-matched. It screens a name against the consolidated US (OFAC), EU, UK, and UN sanctions lists at once, and resolves legal entities against the GLEIF Legal Entity Identifier (LEI) database with corporate-ownership tracing.

All sources are bulk-downloadable, keyless, and clear for redistribution. The server mirrors them to a local SQLite + FTS5 index and serves matches from that mirror — no live API key, no per-request rate limit on the hot path. The agent sees screening verbs (screen_name, resolve_entity, trace_ownership); which list answered a query surfaces only as provenance on each hit.

The matching model is transparent by design: strict token matching first (exact-normalized, then all-tokens-present via FTS5), with a scored Jaro-Winkler + phonetic fuzzy fallback. Approximate hits carry the raw Jaro-Winkler similarity (0–1) — a real measurement, never a fabricated "confidence percentage."

Tools

Six tools organized around two workflows — screen a name against the watchlists, and resolve a legal entity to its global identifier and ownership graph:

| Tool | Description | |:---|:---| | sanctions_screen_name | Screen a name (person, company, vessel, aircraft) against all loaded watchlists at once — OFAC SDN + Consolidated, EU, UK, UN — alias- and fuzzy-aware. Returns scored potential matches with source list, program, designation date, and the matched alias. | | sanctions_get_designation | Fetch the full record for one sanctions designation by source list + entry ID: all aliases, identifiers, addresses, dates/places of birth, nationalities, program, legal basis, and designation date. | | sanctions_resolve_entity | Resolve a company / organization name (+ optional jurisdiction) to ranked candidate GLEIF LEIs. Turns a free-text counterparty name into a stable global identifier. | | sanctions_get_entity | Fetch the full GLEIF Level 1 record for one LEI — legal name, trading names, addresses, registration status, jurisdiction — plus a sanctions cross-reference screened on the legal name. | | sanctions_trace_ownership | Trace the GLEIF Level 2 corporate-ownership graph for an LEI (parents and/or children, BFS to a bounded depth), optionally screening every node for beneficial-ownership screening. | | sanctions_list_sources | List the loaded watchlists and GLEIF datasets with record counts, source URLs, licenses, and the mirror's readiness and as-of timestamps. |

sanctions_screen_name

The 80% entry point — "is this entity on a watchlist?"

• Fans out across all four sanctions lists (OFAC SDN + Consolidated, EU, UK, UN) in one call; the source surfaces only as provenance per hit
• Alias-aware: matches against every published primary name, a.k.a., and f.k.a., not just the canonical name
• Strict mode (default): exact-normalized equality, then all-tokens-present via FTS5 — handles word-order swaps and missing interior words with no fuzzy library
• Fuzzy mode (opt-in, or automatic when strict finds nothing): adds Jaro-Winkler similarity and Double-Metaphone phonetic matching for transliteration-class misses
• Hits labeled exact / strong / approximate; approximate hits carry the raw Jaro-Winkler score (0–1)
• Filter by entity type, source list subset, similarity floor (min_score), and result limit
• On an empty result, returns guidance on how to broaden — and states explicitly that no match is not a clearance

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sanctions_get_designation

The drill-in after sanctions_screen_name surfaces a candidate.

• Full normalized record by source + entry_id (the sourceEntryId from a screen hit)
• All published aliases, structured identifiers (passport / national ID / tax / registration), addresses, dates and places of birth, nationalities, sanctioning program, legal basis, and designation date
• Preserves source sparsity — missing fields mean the source omitted them; the record is never padded with fabricated data

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sanctions_resolve_entity

The bridge from a free-text counterparty name to a stable LEI that the entity tools key off.

• Resolves a company / organization name to ranked GLEIF LEI candidates
• Optional ISO 3166-1 alpha-2 jurisdiction filter and registration-status filter (issued default, lapsed, or any)
• Same strict-then-fuzzy matching model as name screening; approximate hits carry the raw Jaro-Winkler score
• Matches against legal names and published other/trading names

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sanctions_get_entity

Who is this legal entity — plus a watchlist cross-reference in the same call.

• Full GLEIF Level 1 record: legal name, other/trading names, legal and headquarters addresses, registration status, jurisdiction, registration authority and ID, last-update date
• Cross-references the entity's legal name against all loaded watchlists (strict match only — auto-fuzzy on a generic legal name would flood the result with single-common-token false positives)
• LEI input is regex-validated (20 chars: 18 alphanumerics + 2 check digits)

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sanctions_trace_ownership

Beneficial-ownership screening — the cross-source workflow that single-list tools can't do.

• Traverses the GLEIF Level 2 ownership graph breadth-first to a bounded depth (1–5)
• direction: walk parents (who owns it), children (what it owns), or both
• Returns nodes (with role and depth) and directed ownership edges with relationship type
• screenNodes: true screens every entity in the graph against all watchlists — "is anyone in this ownership chain sanctioned?"
• Per-node screen is strict-only and reports screenedNodeCount / flaggedNodeCount so a caller can see coverage at a glance

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Resources and prompts

| Type | Name | Description | |:---|:---|:---| | Resource | sanctions://designation/{source}/{entryId} | One sanctions designation by source + entry ID (URI mirror of sanctions_get_designation). | | Resource | sanctions://entity/{lei} | One GLEIF Level 1 entity by LEI (URI mirror of sanctions_get_entity's entity payload, without the screening cross-reference). | | Resource | sanctions://sources | Loaded lists + GLEIF datasets with counts and refresh timestamps (URI mirror of sanctions_list_sources). | | Prompt | sanctions_vet_counterparty | Sequences the tools into a full counterparty due-diligence pass: resolve → trace ownership → screen the entity and every beneficial owner → summarize with provenance and the decision-support caveat. |

All resource data is also reachable via the tools, which are the primary path for tool-only MCP clients. The resources are a convenience for resource-capable clients only.

Source lists

The server aggregates five upstream sources behind the screening surface. All are bulk, keyless, and clear for redistribution.

| Source | Role | License | |:---|:---|:---| | OFAC SDN + Consolidated (US Treasury) | Primary US sanctions/watchlist — individuals, entities, vessels, aircraft, with a.k.a. aliases | US Government public domain | | EU Consolidated Financial Sanctions List | EU-designated persons and entities | Freely redistributable | | UK Sanctions List (UKSL, FCDO) | UK sanctions targets — persons, entities, ships | Open Government Licence v3.0 | | UN Security Council Consolidated List | UN-designated individuals and entities across all regimes | Freely redistributable | | GLEIF LEI (Level 1 + Level 2) | Who-is-who (entity reference) and who-owns-whom (corporate ownership) | CC0 1.0 Universal |

The UK source is the UK Sanctions List (UKSL), the single authoritative UK source since the OFSI Consolidated List closed on 28 January 2026.

First run: populate the mirror

The mirror is not bundled — the sanctions lists and the GLEIF golden copy are downloaded and normalized on first run. Run the init lifecycle script out-of-band before screening:

bun run mirror:init

This harvests all four sanctions lists in full, rebuilds the per-alias name index, then streams the GLEIF golden copy (Level 1 entities + Level 2 ownership relationships). It is resumable and intended to run once, off the request path.

| Script | Purpose | |:---|:---| | bun run mirror:init | Full initial load of all sources (sanctions lists + GLEIF golden copy). | | bun run mirror:refresh | Re-harvest the sanctions lists and apply GLEIF deltas. The sanctions half (lists + name index) also runs on a cron under HTTP transport; GLEIF deltas are manual. | | bun run mirror:verify | Report mirror readiness and per-source record counts. | | bun run mirror:seed | Load a small synthetic fixture for local smoke tests (no downloads). |

Set SANCTIONS_INIT_SKIP_GLEIF=1 on mirror:init to load only the (small) sanctions lists and skip GLEIF.

GLEIF memory note: the GLEIF Level 1 ingest is the heavy leg — the full golden copy is roughly 3.3M LEI records (~892 MB compressed, several GB decompressed). mirror:init streams and ingests it in bounded batches, so peak resident memory stays modest rather than scaling to the whole decompressed document. The four sanctions lists and the GLEIF deltas / Level 2 ownership data are light by comparison. Size disk for the mirror accordingly, or skip GLEIF with SANCTIONS_INIT_SKIP_GLEIF=1 if you only need watchlist screening.

Features

Built on @cyanheads/mcp-ts-core:

• Declarative tool, resource, and prompt definitions — single file per primitive, framework handles registration and validation
• Unified error handling — handlers throw, framework catches, classifies, and formats
• Typed error contracts with recovery hints (mirror_not_ready, designation_not_found, lei_not_found)
• Pluggable auth: none, jwt, oauth (defaults to none — all data is public)
• Structured logging with optional OpenTelemetry tracing
• STDIO and Streamable HTTP transports

Sanctions-specific:

• Multi-source, workflow-organized surface — one screen fans out across OFAC, EU, UK, and UN internally; sources surface only as provenance
• Local SQLite + FTS5 mirror via the framework MirrorService — offline, no live API key, no per-request rate limit
• Normalized common schema across the four sanctions lists, with a denormalized per-alias name index (one row per name and per alias) so a query matches any of an entity's names in one FTS scan
• Strict-then-fuzzy matching: exact-normalized → all-tokens-present (FTS5) → Jaro-Winkler + Double-Metaphone, capped to bound work on short queries
• GLEIF Level 1 + Level 2 ingest for entity resolution and beneficial-ownership tracing

Agent-friendly output:

• Real signal, not synthetic confidence — approximate hits carry the raw Jaro-Winkler similarity (0–1); strict hits carry a match_type (exact / strong), never a fabricated percentage
• Provenance on every hit — source list, sanctioning program, designation date, the exact name/alias that matched, and its type (primary / aka / fka / low-quality-aka)
• Decision-support caveat carried in every screening tool's output — a hit is a candidate to verify, an empty result is not a clearance
• Freshness surfaced via sanctions_list_sources — each source's record count and the mirror's as-of timestamp, so an agent can judge staleness

Getting started

Public Hosted Instance

A public instance is available at https://sanctions-screening.caseyjhand.com/mcp — no installation required. Point any MCP client at it via Streamable HTTP, with this client config:

{
  "mcpServers": {
    "sanctions-screening-mcp-server": {
      "type": "streamable-http",
      "url": "https://sanctions-screening.caseyjhand.com/mcp"
    }
  }
}

Self-hosted / local

Add the following to your MCP client configuration file. The server is offline-first — populate the mirror with bun run mirror:init before screening (see Source lists).

{
  "mcpServers": {
    "sanctions-screening-mcp-server": {
      "type": "stdio",
      "command": "bunx",
      "args": ["@cyanheads/sanctions-screening-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info"
      }
    }
  }
}

Or with npx (no Bun required):

{
  "mcpServers": {
    "sanctions-screening-mcp-server": {
      "type": "stdio",
      "command": "npx",
      "args": ["-y", "@cyanheads/sanctions-screening-mcp-server@latest"],
      "env": {
        "MCP_TRANSPORT_TYPE": "stdio",
        "MCP_LOG_LEVEL": "info"
      }
    }
  }
}

For Streamable HTTP, set the transport and start the server:

MCP_TRANSPORT_TYPE=http MCP_HTTP_PORT=3010 bun run start:http
# Server listens at http://localhost:3010/mcp

Prerequisites

• Bun v1.3 or higher (or Node.js v24+).
• Disk for the local mirror (the populated SQLite files; GLEIF Level 1 dominates). No API key for any source.

Installation

1. Clone the repository:

git clone https://github.com/cyanheads/sanctions-screening-mcp-server.git

1. Navigate into the directory:

cd sanctions-screening-mcp-server

1. Install dependencies:

bun install

1. Configure environment:

cp .env.example .env
# edit .env if you need to override defaults (all optional)

1. Populate the mirror:

bun run mirror:init

Configuration

All sources are keyless — there is no required API key. Every variable below is optional with a sensible default.

| Variable | Description | Default | |:---|:---|:---| | SANCTIONS_MIRROR_PATH | Filesystem path for the SQLite mirror; a persistent volume on a hosted deployment. | ./data/sanctions.db | | SANCTIONS_REFRESH_CRON | Cron for the scheduled refresh of the sanctions lists + name index (HTTP transport only). GLEIF deltas are refreshed manually via mirror:refresh. | 0 4 * | | SANCTIONS_FUZZY_MIN_SCORE | Default Jaro-Winkler similarity floor for fuzzy matches when min_score is omitted. | 0.85 | | SANCTIONS_FUZZY_MAX_RESULTS | Hard cap on fuzzy candidates scored per query, to bound work on short queries. | 50 | | OFAC_SDN_URL | Override for the OFAC SDN advanced-XML file. | official SLS URL | | OFAC_CONSOLIDATED_URL | Override for the OFAC Consolidated advanced-XML file. | official SLS URL | | EU_FSF_URL | Override for the EU consolidated XML file (includes the static public token path component). | official EU URL | | UK_SANCTIONS_URL | Override for the UK Sanctions List (UKSL) XML file. | official FCDO URL | | UN_SC_URL | Override for the UN Security Council consolidated XML file. | official UN URL | | GLEIF_GOLDEN_COPY_BASE_URL | Override for the GLEIF golden-copy / delta download API. | https://goldencopy.gleif.org | | MCP_TRANSPORT_TYPE | Transport: stdio or http. | stdio | | MCP_HTTP_PORT | Port for the HTTP server. | 3010 | | MCP_LOG_LEVEL | Log level (RFC 5424). | info |

Source URLs default to the verified official endpoints; overrides exist for testing and for pinning a mirror in restricted environments. The EU "token" is a static public path component, not a credential.

See .env.example for the full list of optional overrides.

Running the server

Local development

• Build and run:

  # One-time build
  bun run rebuild

  # Run the built server
  bun run start:stdio
  # or
  bun run start:http

• Run checks and tests:

  bun run devcheck   # Lint, format, typecheck, security, changelog sync
  bun run test       # Vitest test suite
  bun run lint:mcp   # Validate MCP definitions against spec

Docker

docker build -t sanctions-screening-mcp-server .
docker run --rm -p 3010:3010 -v sanctions-data:/usr/src/app/data sanctions-screening-mcp-server

The Dockerfile defaults to HTTP transport, stateless session mode, and logs to /var/log/sanctions-screening-mcp-server. The image runs under Bun, so the mirror uses bun:sqlite (no native build). Mount a volume at the mirror path (/usr/src/app/data by default) so the populated mirror survives container restarts, and run bun run mirror:init inside the container (docker exec) to populate it. OpenTelemetry peer dependencies are installed by default — build with --build-arg OTEL_ENABLED=false to omit them.

Project structure

| Directory | Purpose | |:---|:---| | src/index.ts | createApp() entry point — registers tools/resources/prompts, inits the screening service, schedules the HTTP refresh. | | src/config | Server-specific environment variable parsing and validation with Zod. | | src/mcp-server/tools | Tool definitions (.tool.ts) — the six screening/resolution tools. | | src/mcp-server/resources | Resource definitions (.resource.ts) — the three URI mirrors. | | src/mcp-server/prompts | Prompt definitions (.prompt.ts) — the counterparty vetting prompt. | | src/services/screening | The screening service — local mirror, normalized schema, source ingesters (OFAC/EU/UK/UN/GLEIF), and the strict/fuzzy matching engine. | | scripts/mirror-.ts | Mirror lifecycle CLI — init, refresh, verify, seed. | | tests/ | Unit and integration tests mirroring src/. |

Development guide

See CLAUDE.md/AGENTS.md for development guidelines and architectural rules. The short version:

• Handlers throw, framework catches — no try/catch in tool logic
• Use ctx.log for request-scoped logging, ctx.state for tenant-scoped storage
• Register new tools and resources via the barrels in src/mcp-server/*/definitions/index.ts
• Wrap external sources: validate raw → normalize to the common schema → return the output schema; never fabricate fields a source omits, and never synthesize a confidence score

Attribution

This server redistributes open data from the following sources, cited here per their terms:

• OFAC SDN and Consolidated lists — US Department of the Treasury, Office of Foreign Assets Control (US Government public domain).
• EU Consolidated Financial Sanctions List — European Commission / EEAS (freely redistributable).
• UK Sanctions List — UK Foreign, Commonwealth & Development Office, licensed under the Open Government Licence v3.0 (attribution required).
• UN Security Council Consolidated List — United Nations Security Council (freely redistributable).
• GLEIF LEI data — Global Legal Entity Identifier Foundation, CC0 1.0 Universal.

Contributing

Issues and pull requests are welcome. Run checks and tests before submitting:

bun run devcheck
bun run test

License

Apache-2.0 — see LICENSE for details.