Kill-switch

Stop an agent instantly. Three levels: freeze spending, revoke auth, terminate agent.

When something goes wrong with an agent in production, you need to stop it immediately — often before you fully understand what happened. Sly offers three graduated kill-switch levels, each faster and more drastic than the last.

The three levels

Level	Command	Effect	When to use
1. Freeze wallet	POST /v1/agent-wallets/:id/freeze	Agent can’t spend; auth, reads, SSE still work	First response to suspected misbehavior
2. Revoke auth key	DELETE /v1/agents/:id/auth-keys	Agent can’t authenticate at all	Confirmed credential compromise
3. Terminate agent	DELETE /v1/agents/:id	Agent permanently removed	Post-incident cleanup; unrecoverable

All three are instant on the live path (though cached tokens may take up to 60 seconds to fully expire — see auth caveats).

Level 1: Freeze

Safe, reversible, preserves forensic capability. The agent stays logged in, can read data, can emit events — it just can’t move money.

curl -X POST https://api.getsly.ai/v1/agent-wallets/$AGENT_WALLET_ID/freeze \
  -H "Authorization: Bearer pk_live_..." \
  -d '{ "reason": "Unusual spending pattern detected at 14:22 UTC" }'

Effects:

• All spending attempts return 403 WALLET_FROZEN
• Streams pause (no accrual)
• Scheduled transfers fail at their scheduled time
• Agent can still authenticate, read balances, receive SSE events
• Audit log preserved

Unfreeze:

curl -X POST https://api.getsly.ai/v1/agent-wallets/$AGENT_WALLET_ID/unfreeze \
  -d '{ "acknowledgment": "Reviewed logs — false alarm, resuming" }'

Use freeze first. In most incidents this is enough — you stop the bleeding, investigate, and either unfreeze or escalate.

Level 2: Revoke auth key

Confirmed compromise. The agent (or an attacker with the agent’s credentials) can no longer authenticate.

curl -X DELETE https://api.getsly.ai/v1/agents/$AGENT_ID/auth-keys \
  -H "Authorization: Bearer pk_live_..."

Effects:

• All active sess_* tokens invalidated
• Ed25519 public key removed — challenge-response fails
• Agent token (agent_*) remains valid (it’s a separate credential) — rotate it too if compromise is suspected at that level:

curl -X POST https://api.getsly.ai/v1/agents/$AGENT_ID/rotate-token \
  -H "Authorization: Bearer pk_live_..."

The agent record stays — you can provision fresh credentials and put the agent back online once the incident is resolved.

Level 3: Terminate

Last resort. Permanent.

curl -X DELETE https://api.getsly.ai/v1/agents/$AGENT_ID \
  -H "Authorization: Bearer pk_live_..."

Effects:

• Agent record marked revoked (tombstoned for audit)
• All credentials revoked
• Wallets disassociated (funds remain — terminating an agent does not forfeit funds)
• Policy, mandates, streams cancelled

Terminated agents cannot be un-terminated. Create a new agent with fresh credentials if you want to continue.

Kill-switch operator

For Tier 3 (Trusted) agents, Sly requires a named kill-switch operator — a human who can execute these actions. The operator’s contact is recorded in the agent’s policy:

{
  "kill_switch": {
    "operators": ["[e-mail]"],
    "contacts": ["+1-555-..."],
    "notification_channels": ["slack", "sms"]
  }
}

When freeze / revoke / terminate events fire, Sly notifies the listed operators immediately through their configured channels. This is true even if the action was triggered by Sly-side automation (e.g. fraud detection auto-freezing).

Automated freezes

Sly can auto-freeze an agent on certain signals:

• Velocity violations — too many transactions in too short a window
• Policy-drift alerts — sudden behavior change compared to baseline
• External signals — integrated threat feeds (sanctions list hits, known-bad addresses)
• Customer-initiated — one-click freeze from the Sly dashboard

Auto-freezes always send notifications and log the triggering signal. Human review is required to unfreeze.

Incident runbook

When something looks wrong:

1. Freeze the wallet

   POST /v1/agent-wallets/:id/freeze — stops further spending.

2. Query the evaluation log

   GET /v1/agent-wallets/:id/evaluations — see what the agent was attempting and what was allowed vs. blocked.

3. Read recent transfers

   GET /v1/agents/:id/transactions — audit what actually executed.

4. Decide

   If the behavior was intended (new deployment, new merchant): unfreeze. If not, revoke auth and investigate.

5. Restore or terminate

   Either provision a new keypair and resume, or terminate the agent.

Testing the kill-switch

Before going live, actually exercise all three levels in sandbox. Include a kill-switch drill in your deployment checklist. An incident is the worst time to discover your freeze script has a typo.