langchain-verigent

Trust verification for LangChain agents, chains, and tools using Verigent keys.

The problem

Multi-agent LangChain pipelines delegate tasks to sub-agents and tools with no way to verify trust, capability, or identity. Any agent can claim any role. langchain-verigent adds cryptographic trust verification to your pipeline — every agent carries a VG key that declares what it is and what it can do.

Install

pip install langchain-verigent

Quick start

Callback handler (recommended)

Attach to any agent executor to automatically verify VG keys on tool calls:

from langchain_verigent import VerigentCallbackHandler

handler = VerigentCallbackHandler(
    min_tier=2,          # Require at least V2
    threshold=0.5,       # 50% composite trust minimum
    block_untrusted=True # Raise TrustDeniedError on failure
)

# Attach to your agent
result = agent_executor.invoke(
    {"input": "Research this topic"},
    config={"callbacks": [handler]}
)

# Inspect trust decisions
for entry in handler.trust_log:
    print(f"{entry['handle']}: {entry['composite']}% — {'PASS' if entry['passed'] else 'FAIL'}")

Tool wrapper

Wrap any tool to attach a VG key and verify trust before execution:

from langchain_verigent import VerigentToolWrapper
from langchain_community.tools import TavilySearchResults

search = TavilySearchResults()
trusted_search = VerigentToolWrapper(
    search,
    vg_key="VG:SEARCH-01:V3-SENT·Se4Op7An5Ar9Co2Ad6St8Sc3Sa5So1Br2Fo6",
    threshold=0.4
)

result = trusted_search.invoke("latest AI papers")
print(f"Trust: {trusted_search.trust_score.percent}%")

Agent filter (multi-agent)

Filter and rank agents by trust score:

from langchain_verigent import VerigentAgentFilter

agents = [
    {"name": "researcher", "vg_key": "VG:RES-01:V4-ANAL·Se4Op7An5Ar9Co2Ad6St8Sc3Sa5So1Br2Fo6"},
    {"name": "writer",     "vg_key": "VG:WRT-02:V2-SAGE·Se2Op3An4Ar2Co5Ad3St4Sc2Sa8So1Br3Fo2"},
    {"name": "untrusted",  "vg_key": "VG:BAD-99:V0-SENT·Se1Op1An1Ar1Co1Ad1St1Sc1Sa1So1Br1Fo1"},
]

filter = VerigentAgentFilter(min_tier=2, threshold=0.4)

# Only agents meeting threshold
trusted = filter.filter(agents)  # [researcher, writer]

# Ranked by composite score
ranked = filter.rank(agents)  # [researcher, writer, untrusted]

VG Key format

VG:{NAME}-{SUFFIX}:{TIER}-{PRIMARY}·{12×class_code+digit}

• Tier: V0 (unverified) through V6 (sovereign-grade)
• Primary: 4-letter class code (e.g. ARCH, SENT, ANAL)
• Scores: 12 class dimensions, each 0-9

Classes: Sentinel, Operative, Analyst, Architect, Conduit, Adaptor, Steward, Scout, Sage, Sovereign, Broker, Forge.

Configuration

Links

• Verigent — Agent trust verification
• GitHub
• LangChain

License

MIT