Snapback Selfheal MCP Server

Snapback self-heal interceptor for OpenClaw

Make Snapback automatic. Instead of remembering to call the diagnosis tool, wrap your agent's tool calls once — and every error is auto-diagnosed, and gated-safe fixes are applied and retried without a human.

"Power tools are optional. Infrastructure is not." This turns Snapback from a tool you reach for into infrastructure that runs on every failure.

What it does

On any tool-call error, the interceptor:

1. Calls diagnose_infra_error (free, no token, no LLM, <150ms).
2. Applies the three-factor gate — auto-apply a fix only when all are true:
   • confidence >= 0.85
   • source == "library" (a curated verified fix, not an LLM guess)
   • auto_safe == true (the fix is retry / refetch / config — reversible, side-effect-free)
3. If the gate passes → applies the fix and retries once. If it fails → escalates to a human (logs the verdict). It never auto-applies a mutate or destructive fix (create/change state, money, auth grants).

It fails closed: when unsure, it escalates rather than acting.

Install

# no install needed beyond the stdlib; drop the file in, or:
cp snapback_interceptor.py your_agent/
export SNAPBACK_MCP=https://api.snapback.sh/mcp   # default; the free tools need no token

Use

from snapback_interceptor import SnapbackInterceptor

heal = SnapbackInterceptor(
    auto_apply=True,
    on_escalate=lambda v: my_ops_inbox.log(v),   # human sees non-auto-safe verdicts
    on_heal=lambda v: metrics.count("snapback.autoheal", family=v["family"]),
)

# wrap any call that might raise:
result = heal.run(call_solana_rpc, wallet, amount)

# or as a decorator:
@heal.guard
def call_solana_rpc(wallet, amount): ...

# or manually on a caught error:
verdict = heal.diagnose("BlockhashNotFound")
if verdict["gate"]["auto_apply_ok"]:
    ...apply verdict["fix"] and retry...

The gate contract (returned by Snapback)

diagnose_infra_error returns {matched, family, fix, confidence, source, action_class, auto_safe, gate}. action_class is one of:

gate.auto_apply_ok is the ready-made verdict; the interceptor also re-derives it locally so a stale client can't over-trust.

Privacy & safety

• 100% client-side. Talks only to the free public diagnose_infra_error endpoint.
• Never sends your Snapback token for the diagnosis (diagnosis is free).
• Snapback scrubs trace content server-side; this sends only the error string you pass.
• Composes with bridge.py (post-mortem forwarding) — this is the live auto-heal layer.

Roadmap

• submit_feedback on the retry outcome (did the fix work?) → feeds the shared library (the network effect).
• Hermes + LangChain adapters (same gate, different framework hook).