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SafeAgent

azender1/safeagent
6STDIOregistry active
Summary

This is an exactly-once execution guard that prevents AI agents from firing duplicate tool calls when Claude retries after errors or crashes. It exposes a /claim endpoint that returns PROCEED on the first call for a given request_id and SKIP on any repeat, blocking double charges, duplicate emails, or repeated orders. The server runs on Railway with pay-per-call pricing via x402 ($0.001 per claim), plus a free /claim/test endpoint for integration testing. Also includes a local SQLite guard you can embed directly in Python agents. The repo shows a real trading bot that prevented duplicate buy orders across 23 executions using stable keys derived from symbol, side, quantity, and bar timestamp. Useful when you're building agents that interact with payment APIs, email services, webhooks, or any broker where firing the same action twice causes real problems.

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SafeAgent — Execution Guard for AI Agents

SafeAgent — Exactly-Once Execution for AI Agents

Pay per claim via x402.
POST /claim · $0.001 · Base + Solana · safeagent-production.up.railway.app

# Paid endpoint (x402)
curl -s -X POST https://safeagent-production.up.railway.app/claim \
  -H "Content-Type: application/json" \
  -H "x-payment: <Base or Solana payment>" \
  -d '{"request_id":"order:TQQQ:buy:6:2026-05-19T13:31:00-04:00","action":"order"}'
# → {"status":"PROCEED"|"SKIP","request_id":"..."}

# Free test endpoint — verify your integration before paying (10 calls per IP)
curl -s -X POST https://safeagent-production.up.railway.app/claim/test \
  -H "Content-Type: application/json" \
  -d '{"agent_id":"bot-1","action_type":"order","scope":"TQQQ:buy:bar:2026-05-19T13:31:00-04:00"}'
# → {"status":"PROCEED"|"SKIP","request_id":"...","test":true,"calls_remaining":9}

Indexed on Bazaar. 102 requests / 7 days.


Verified on Soma

SafeAgent is the first verified external integrator on Soma — the Mycelium agent catalog. Every production execution is anchored on-chain via Mycelium Trails and independently verifiable without going through the operator.

  • Integrator badge — verified external client running Mycelium Trails in production
  • Live trails — https://argentum-api.rgiskard.xyz/dashboard/trails?client=safeagent-prod
  • Public audit — any auditor can verify SafeAgent executions independently

What it does

SafeAgent is an exactly-once execution guard. It prevents AI agents and SaaS applications from firing the same action twice — on crash-retry, duplicate signal, webhook replay, or concurrent execution across multiple instances.

Every action gets a stable request_id derived from what the agent is doing and when. The first call commits. Every subsequent call with the same key returns SKIP and the original result. No double charges. No double emails. No double orders. No duplicate webhooks.

State machine: PENDING → COMMITTED | SKIP

Common failure modes SafeAgent prevents:

ScenarioWithout SafeAgentWith SafeAgent
Stripe charge times out, retry firesCustomer charged twiceSecond charge returns SKIP
Welcome email on signup retriedUser gets two welcome emailsSecond send returns SKIP
Webhook delivered twice (Stripe/GitHub/Twilio guarantee at-least-once)Event processed twiceSecond processing returns SKIP
Workspace provisioned on retryTwo workspaces createdSecond provision returns SKIP
AI agent tool call retried after crashDuplicate side effectSecond call returns SKIP

x402 API

POST /claim

Gate an action. Returns PROCEED on first call, SKIP on any repeat.

curl -s -X POST https://safeagent-production.up.railway.app/claim \
  -H "Content-Type: application/json" \
  -H "x-payment: <payment>" \
  -d '{"request_id":"order:TQQQ:buy:6:2026-05-19T13:31:00-04:00","action":"order"}'
{ "status": "PROCEED", "request_id": "order:TQQQ:buy:6:2026-05-19T13:31:00-04:00" }

Retry with the same payload:

{ "status": "SKIP", "request_id": "order:TQQQ:buy:6:2026-05-19T13:31:00-04:00", "existing": "..." }

POST /claim/test

Free test endpoint — same logic, no payment required. Limited to 10 calls per IP total.

curl -s -X POST https://safeagent-production.up.railway.app/claim/test \
  -H "Content-Type: application/json" \
  -d '{"agent_id":"bot-1","action_type":"order","scope":"TQQQ:buy:6:bar:2026-05-19T13:31:00-04:00"}'
{ "status": "PROCEED", "request_id": "...", "test": true, "calls_remaining": 9 }

GET /audit

Full claim history. Filter by agent_id, action, status, or timestamp range.

curl "https://safeagent-production.up.railway.app/audit?agent_id=bot-1&status=COMMITTED"
{"items": [...], "total": 5, "limit": 100, "offset": 0}

Parameters: agent_id, action, status, from_ts, to_ts, limit (max 1000), offset.


Local guard (embedded SQLite)

The same guarantee without the network call. Drop this into any Python agent:

import sqlite3

_SA_DB = "safeagent_orders.db"
_sa_con = sqlite3.connect(_SA_DB, check_same_thread=False)
_sa_con.execute("""CREATE TABLE IF NOT EXISTS orders (
    request_id TEXT PRIMARY KEY,
    result     TEXT,
    status     TEXT DEFAULT 'PENDING',
    created_at TEXT DEFAULT (datetime('now'))
)""")
_sa_con.commit()

def place_order_with_guard(symbol, qty, side, bar_ts):
    request_id = f"order:{symbol}:{side}:{qty}:{bar_ts}"

    _sa_con.execute(
        "INSERT OR IGNORE INTO orders (request_id, status) VALUES (?, 'PENDING')",
        (request_id,)
    )
    _sa_con.commit()

    row = _sa_con.execute(
        "SELECT status, result FROM orders WHERE request_id = ?",
        (request_id,)
    ).fetchone()

    if row and row[0] == 'COMMITTED':
        print(f"SAFEAGENT SKIP: {request_id}")
        return row[1]

    result = place_order(symbol, qty, side)

    _sa_con.execute(
        "UPDATE orders SET status='COMMITTED', result=? WHERE request_id=?",
        (json.dumps(str(result)), request_id)
    )
    _sa_con.commit()
    return result

The request_id is stable: same symbol, same side, same quantity, same bar timestamp = same key. If the bot crashes between firing and settling, the next run sees PENDING, re-fires, and settles. If it crashed after settling, the next run sees COMMITTED and returns SKIP.


Case study: crash-retry duplicate prevention

What actually happens without a guard.

A trading bot fires a market order to buy 6 shares of TQQQ. The broker accepts it. The bot crashes before updating state. On restart — same signal, same bar — the bot fires again. The broker fills it twice. The agent now holds 12 shares when it intended to hold 6.

This is not theoretical. It happens on any unhandled exception between order submission and state persistence.

How SafeAgent blocks it.

The guard derives a stable key from the order parameters before touching the broker: request_id = f"order:{symbol}:{side}:{qty}:{bar_ts}" e.g. "order:TQQQ:buy:6:2026-05-19T13:31:00-04:00"

Then:

  1. INSERT OR IGNORE — atomic, no-op if the key already exists
  2. Check status — if COMMITTED, return cached result immediately
  3. Fire order — only reaches the broker if step 2 passed
  4. Settle — write COMMITTED + broker response

On crash between steps 3 and 4: key is PENDING. Next run re-fires. This is safe — PENDING means the order may or may not have landed. The broker's own idempotency (duplicate client_order_id) handles the edge case.

On crash after step 4: key is COMMITTED. Next run hits step 2, logs SAFEAGENT SKIP, returns the original order. The broker is never touched again.

Live proof from May 19 session.

safeagent_orders.db — 23 orders, 23 COMMITTED, 0 PENDING.

order:TQQQ:buy:6:2026-05-19T13:31:00-04:00          COMMITTED
order:TQQQ:sell:18:2026-05-19T13:25:00-04:00:TRAIL   COMMITTED
order:SQQQ:buy:11:2026-05-19T13:54:00-04:00          COMMITTED
order:SQQQ:sell:22:2026-05-19T14:00:00-04:00:V20     COMMITTED
order:TQQQ:buy:6:2026-05-19T14:02:00-04:00           COMMITTED
order:TQQQ:buy:6:2026-05-19T14:05:00-04:00           COMMITTED
order:TQQQ:sell:12:2026-05-19T14:18:00-04:00:V20     COMMITTED
order:SQQQ:buy:11:2026-05-19T14:20:00-04:00          COMMITTED
order:SQQQ:sell:11:2026-05-19T14:26:00-04:00:V20     COMMITTED
order:TQQQ:buy:6:2026-05-19T14:26:00-04:00           COMMITTED
order:TQQQ:sell:6:2026-05-19T14:31:00-04:00:FLIP     COMMITTED
order:SQQQ:buy:11:2026-05-19T14:31:00-04:00          COMMITTED
order:SQQQ:buy:11:2026-05-19T14:42:00-04:00          COMMITTED
order:SQQQ:buy:11:2026-05-19T14:53:00-04:00          COMMITTED
order:SQQQ:sell:33:2026-05-19T15:00:00-04:00:TRAIL   COMMITTED
order:SQQQ:buy:11:2026-05-19T15:03:00-04:00          COMMITTED
order:SQQQ:sell:11:2026-05-19T15:10:00-04:00:V20     COMMITTED
order:TQQQ:buy:6:2026-05-19T15:14:00-04:00           COMMITTED
order:TQQQ:sell:12:2026-05-19T15:20:00-04:00:V20     COMMITTED
... (23 total)

Every order that fired is in the db as COMMITTED. If either bot instance had crashed mid-flight and restarted with the same signal, it would have hit the COMMITTED row and stopped. The broker would never have seen a duplicate submission.

The two-bot scenario.

Two instances of the same bot ran against the same shared safeagent_orders.db. They operated on different timelines — bot 1 entered the morning bull wave at 12:32, bot 2 was blocked by the broker's open-position check and entered later at 13:31. They never tried to fire the same request_id because they were acting on different bars.

The scenario where the db guard fires instead of the broker check: two bots on separate broker accounts, both wired to the same safeagent_orders.db, both reading the same bar signal at the same second. Bot 1 fires INSERT OR IGNORE and wins the atomic write. Bot 2 fires the same insert — SQLite's INSERT OR IGNORE drops it silently. Bot 2 reads the row, sees PENDING, and proceeds to fire. Both orders land.

This is the gap. INSERT OR IGNORE + status check handles crash-retry cleanly. For true concurrent multi-agent deduplication, the status check needs to happen inside a transaction with a row-level lock, or the guard needs to be the hosted endpoint where the write is serialized server-side.

The hosted /claim endpoint is that serialization layer.


Case study: live duplicate blocking — May 21, 2026

Six confirmed SKIP events from a live session on the full stack: DashClaw, SafeAgent, Mycelium Trails, Base/Arbitrum, broker Alpaca.

  • 0942 ET: duplicate buy TQQQ qty=6 blocked, $452
  • 0947 ET: duplicate add TQQQ qty=6 blocked, $452
  • 0949 ET: duplicate sell TQQQ qty=12 on flip, $902
  • 1000 ET: duplicate entry TQQQ qty=6 blocked, $454
  • 1014 ET: duplicate sell TQQQ qty=18 on V20 flip, $1,350
  • 1106 ET: duplicate SQQQ add during scale-in, $43

Gap surfaced: exit side has no guard.

At 1114 ET a legitimate SQQQ exit failed with 422 Unprocessable Entity after three retries. Broker API continued reporting an open TQQQ position. Bot logged ENTRY BLOCKED from 1133 through 1400 — three hours of blocked entries from a phantom position. Those blocks appear in any receipt chain as legitimate decisions with no trace of the upstream failure.

Exit-side exactly-once semantics are the next spec item.

Full session data: https://gist.github.com/azender1/b9112b6519c935df4a75cb05cd250e26


Integration

Python (local db)

Copy the guard block from the source above into place_order_with_retry. Works with any broker. No network dependency.

CrewAI

from crewai import Agent
import sqlite3

guard_con = sqlite3.connect("safeagent_orders.db", check_same_thread=False)
# ... same guard pattern, keyed on tool_name + input hash + session_id

PR crewAIInc/crewAI#5822 adds pluggable idempotency backends. SafeAgent's SQLite schema is compatible.

x402 (hosted)

import requests

def claim(agent_id, action_type, scope, payment_header):
    r = requests.post(
        "https://safeagent-production.up.railway.app/claim",
        headers={"x-payment": payment_header, "Content-Type": "application/json"},
        json={"agent_id": agent_id, "action_type": action_type, "scope": scope}
    )
    return r.json()  # {"status": "COMMITTED"|"SKIP", "request_id": "..."}

SaaS (Stripe / email / webhooks)

The same guard works for any SaaS side effect. Wrap your Stripe charge, email send, or webhook handler:

import requests

def safe_stripe_charge(customer_id, amount, idempotency_key, payment_header):
    # Gate before touching Stripe
    r = requests.post(
        "https://safeagent-production.up.railway.app/claim",
        headers={"x-payment": payment_header, "Content-Type": "application/json"},
        json={
            "agent_id": "saas-billing",
            "action_type": "stripe_charge",
            "scope": f"customer:{customer_id}:amount:{amount}:key:{idempotency_key}"
        }
    )
    result = r.json()
    if result["status"] == "SKIP":
        return result["cached_result"]  # Return original charge, don't hit Stripe again

    charge = stripe.PaymentIntent.create(amount=amount, customer=customer_id)
    # Settle with result
    return charge

Same pattern for email sends, webhook processing, and resource provisioning. Any action that must not fire twice gets a claim before execution.

Webhook deduplication — Stripe, GitHub, and Twilio all guarantee at-least-once delivery. SafeAgent turns at-least-once into exactly-once:

def handle_stripe_webhook(event):
    r = requests.post(
        "https://safeagent-production.up.railway.app/claim",
        headers={"x-payment": payment_header, "Content-Type": "application/json"},
        json={
            "agent_id": "saas-webhooks",
            "action_type": "stripe_event",
            "scope": event["id"]  # Stripe event ID is stable across retries
        }
    )
    if r.json()["status"] == "SKIP":
        return {"ok": True}  # Already processed

    # Process event once
    provision_subscription(event)

WisePick

WisePick is a deterministic routing layer for agent runtimes. The integration splits capability selection from durable, idempotent execution — WisePick answers what and which provider, SafeAgent answers whether this logical work already ran.

Stack:

WisePick /v1/decide → DashClaw → SafeAgent → Mycelium Trails → Base/Arbitrum

How request_id is derived:

WisePick's adapter derives the SafeAgent request_id from the stable turn anchor — session_id, turn_id, start_time_ms, normalized task, capability_id, provider, and constraints. The WisePick decision_id is intentionally excluded, so a retry that mints a new decision_id still maps to the same SafeAgent execution slot and returns SKIP rather than re-executing the side effect.

This maps to the task_fingerprint / startTime_ms fields in SafeAgent's dispatch payload (mcp.safeagent_execution.v1).

  • Adapter: adapters/safeagent_adapter.py
  • Integration docs: docs/integrations/safeagent.md
  • Replay demo (RUN → SKIP, no HTTP required): examples/safeagent_replay_demo.py
  • Integration thread: SafeAgent #9

Stack

DashClaw (attribution + approval) → decision_id
└── SafeAgent (exactly-once guard) → request_id
    └── Mycelium Trails (on-chain receipt) → action_ref → Base/Arbitrum

Canonical action_ref derivation — JCS (RFC 8785), aligned with argentum-core, Nobulex, and APS:

import hashlib
import json

def compute_action_ref(
    agent_id: str,
    action_type: str,
    scope: str,
    timestamp: str,  # RFC 3339 UTC, 3-digit ms: "2026-05-15T10:00:00.123Z"
) -> str:
    payload = {
        "agent_id": agent_id,
        "action_type": action_type,
        "scope": scope,
        "timestamp": timestamp,
    }
    # JCS (RFC 8785): lexicographic key order, no spaces, UTF-8
    canonical = json.dumps(
        dict(sorted(payload.items())),
        separators=(",", ":"),
        ensure_ascii=False,
    ).encode("utf-8")
    return hashlib.sha256(canonical).hexdigest()

Note on timestamp format: timestamp is an RFC 3339 UTC string with exactly 3 millisecond digits — "2026-05-15T10:00:00.123Z". The trailing Z is mandatory. Do not pass an epoch-millisecond integer; convert first:

import datetime

def format_timestamp(dt: datetime.datetime) -> str:
    ms = dt.microsecond // 1000
    return dt.strftime(f"%Y-%m-%dT%H:%M:%S.{ms:03d}Z")

Conformance fixtures: giskard09/argentum-core tag action-ref-v1.0


Deployment

Railway · Serverless OFF · always-on
PyPI: pip install safeagent-exec-guard
npm: npm install n8n-nodes-safeagent
MCP Registry: io.github.azender1/safeagent


License

Apache-2.0

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Registryactive
Packagesafeagent-exec-guard
TransportSTDIO
UpdatedApr 26, 2026
View on GitHub