# nonce_fill_gap

Fill a nonce gap by sending a minimal STX transfer at the specified nonce. LAST-RESORT recovery action. Each gap-fill is a real on-chain transaction with a real fee (~0.001-0.01 STX). Most gaps self-resolve within seconds as Stacks blocks are 3-5s. Only use this after confirming the gap persists via nonce_health. When transactions are pending but a gap exists in the nonce sequence (e.g., nonces 5 and 7 are pending but 6 is missing), the Stacks mempool will not process nonces 7+ until 6 is filled. This tool fills the gap with a 1 micro-STX transfer to the PoX burn address. Use nonce_health first to identify gaps, then call this tool for each missing nonce. Requires the wallet to be unlocked. The fee is auto-estimated.

Agent View of the PolicyLayer registry record for `nonce_fill_gap`. HTML page: https://policylayer.com/tools/io-github-aibtcdev-mcp-server/nonce-fill-gap

## Facts

- Tool: `nonce_fill_gap`
- Server: Aibtc (`aibtcdev/aibtc-mcp-server`) — https://policylayer.com/tools/io-github-aibtcdev-mcp-server.md
- Homepage: https://github.com/aibtcdev/aibtc-mcp-server
- Risk category: Financial (Critical risk)
- Registry record: grade F, identity verified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Approval-gated

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "nonce_fill_gap",
    "arguments": {}
  }
}
```

## Why nonce_fill_gap is rated Critical

This tool submits real on-chain blockchain transactions that spend STX tokens (both the transfer amount and transaction fees). It commits financial value irreversibly on-chain, qualifying it as Financial. The funds sent to the PoX burn address are unrecoverable, adding a destructive element, but the primary action is a financial transaction on a blockchain network.

From the tool's own definition: "Fill a nonce gap by sending a minimal STX transfer at the specified nonce... Each gap-fill is a real on-chain transaction with a real fee (~0.001-0.01 STX)... fills the gap with a 1 micro-STX transfer to the PoX burn address."

## Use case

AI agents use nonce_fill_gap to commit financial operations through Aibtc, usually the final step of a payment, billing, or trading workflow. A call moves real money.

## Recommended policy (PolicyLayer)

Verdict: **Approval-gated**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Aibtc:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "nonce_fill_gap": {
      "deny_if": [
        {
          "conditions": [],
          "on_deny": "Requires human approval."
        }
      ]
    }
  }
}
```

## Other tools on Aibtc (357)

- `bitflow_cancel_order` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/bitflow-cancel-order.md
- `bounty_cancel` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/bounty-cancel.md
- `credentials_delete` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/credentials-delete.md
- `delete_hiro_api_key` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/delete-hiro-api-key.md
- `identity_unset_wallet` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/identity-unset-wallet.md
- `jingswap_cancel_cycle` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/jingswap-cancel-cycle.md
- `jingswap_cancel_sbtc` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/jingswap-cancel-sbtc.md
- `lightning_lock` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/lightning-lock.md
- `ordinals_p2p_cancel` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/ordinals-p2p-cancel.md
- `pillar_direct_revoke_fast_pool` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/pillar-direct-revoke-fast-pool.md
- `reputation_revoke_feedback` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/reputation-revoke-feedback.md
- `stackspot_cancel_pot` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/stackspot-cancel-pot.md
- `wallet_delete` — Destructive — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/wallet-delete.md
- `broadcast_transaction` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/broadcast-transaction.md
- `btc_sign_message` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/btc-sign-message.md
- `call_contract` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/call-contract.md
- `deploy_contract` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/deploy-contract.md
- `dual_stacking_opt_out` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/dual-stacking-opt-out.md
- `inference_check_provider` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/inference-check-provider.md
- `inscribe_child_reveal` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/inscribe-child-reveal.md
- `inscribe_reveal` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/inscribe-reveal.md
- `jingswap_close_deposits` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/jingswap-close-deposits.md
- `jingswap_settle_with_refresh` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/jingswap-settle-with-refresh.md
- `lightning_unlock` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/lightning-unlock.md
- `news_publisher_compile_brief` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/news-publisher-compile-brief.md
- `nonce_heal` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/nonce-heal.md
- `nostr_sign_event` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/nostr-sign-event.md
- `pillar_connect` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/pillar-connect.md
- `pillar_key_generate` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/pillar-key-generate.md
- `pillar_key_lock` — Execute — https://policylayer.com/tools/io-github-aibtcdev-mcp-server/pillar-key-lock.md
- …and 327 more: https://policylayer.com/tools/io-github-aibtcdev-mcp-server.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-github-aibtcdev-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-aibtcdev-mcp-server