edictum 0.5.4

Runtime safety for AI agents. Stop agents before they break things.

Edictum

Runtime contract enforcement for AI agent tool calls.

AI agents call tools with real-world side effects -- reading files, querying databases, executing commands. The standard defense is prompt engineering, but prompts are suggestions the LLM can ignore. Edictum enforces contracts at the decision-to-action seam: before a tool call executes, Edictum checks it against YAML contracts and denies it if it violates policy. The agent cannot bypass it.

This is not feature flags. This is not prompt guardrails. Edictum is a deterministic enforcement point for tool calls -- preconditions before execution, postconditions after, session limits across turns, and a full audit trail.

Show Me

contracts.yaml

apiVersion: edictum/v1
kind: ContractBundle

metadata:
  name: my-policy

defaults:
  mode: enforce

contracts:
  - id: block-sensitive-reads
    type: pre
    tool: read_file
    when:
      args.path:
        contains_any: [".env", ".secret", "credentials", ".pem", "id_rsa"]
    then:
      effect: deny
      message: "Sensitive file '{args.path}' denied."
      tags: [secrets, dlp]

Python

import asyncio
from edictum import Edictum, EdictumDenied

async def read_file_fn(path):
    return open(path).read()

async def main():
    guard = Edictum.from_yaml("contracts.yaml")

    try:
        result = await guard.run("read_file", {"path": "/app/config.json"}, read_file_fn)
        print(result)
    except EdictumDenied as e:
        print(f"Denied: {e}")

asyncio.run(main())

CLI

$ edictum validate contracts.yaml
  contracts.yaml -- 1 contract (1 pre)

$ edictum check contracts.yaml --tool read_file --args '{"path": ".env"}'
  DENIED by block-sensitive-reads
   Message: Sensitive file '.env' denied.
   Tags: secrets, dlp
   Rules evaluated: 1

Framework integration (one adapter, same contracts)

from edictum import Edictum, Principal
from edictum.adapters.langchain import LangChainAdapter

guard = Edictum.from_yaml("contracts.yaml")
adapter = LangChainAdapter(guard, principal=Principal(role="analyst"))
wrapper = adapter.as_tool_wrapper()
# Wraps any LangChain tool -- preconditions, audit, and session limits apply automatically

How It Works

1. Write contracts in YAML. Preconditions deny dangerous calls before execution. Postconditions check tool output after. Session limits cap total calls and retries.
2. Attach to your agent framework. One adapter line. Same contracts across all six frameworks.
3. Every tool call passes through the pipeline. Preconditions, session limits, and principal context are evaluated. If any contract fails, the call is denied and never executes.
4. Full audit trail. Every evaluation produces a structured event with automatic secret redaction.

How It Compares

Approach	Scope	Runtime enforcement	Audit trail
Prompt/output guardrails	Input/output text	No -- advisory only	No
API gateways / MCP proxies	Network transport	Yes -- at the proxy	Partial
Security scanners	Post-hoc analysis	No -- detection only	Yes
Manual if-statements	Per-tool, ad hoc	Yes -- scattered logic	No
Edictum	Tool call contracts	Yes -- deterministic pipeline	Yes -- structured + redacted

Framework Support

Edictum integrates with six agent frameworks. Same YAML contracts, same enforcement, different adapter patterns:

Framework	Integration	PII Redaction	Complexity
LangChain + LangGraph	as_tool_wrapper()	Full interception	Low
OpenAI Agents SDK	as_guardrails()	Logged only	Medium
Agno	as_tool_hook()	Full interception	Low
Semantic Kernel	register()	Full interception	Medium-High
CrewAI	register()	Partial	High
Claude Agent SDK	to_sdk_hooks()	Logged only	Low

See Adapter Docs for setup, known limitations, and recommendations.

Install

Requires Python 3.11+. Current version: v0.5.4.

pip install edictum              # core (zero deps)
pip install edictum[yaml]        # + YAML contract engine
pip install edictum[otel]        # + OpenTelemetry span emission
pip install edictum[cli]         # + validate/check/diff/replay CLI
pip install edictum[all]         # everything

Built-in Templates

guard = Edictum.from_template("file-agent")      # secret file protection, destructive cmd blocking
guard = Edictum.from_template("research-agent")   # output PII detection, session limits
guard = Edictum.from_template("devops-agent")     # role gates, ticket requirements, bash safety

Demos & Examples

• edictum-demo -- Full scenario demos, adversarial tests, benchmarks, and Grafana observability
• Contract Patterns -- Real-world contract recipes by concern
• Framework Adapters -- Integration guides for six frameworks

Links

• Documentation
• GitHub
• PyPI
• Changelog
• License (MIT)