LIGHTNING-CHECK(7)

💅 LIGHTNING-CHECK(7) — the check page, bestie ✨

okay so this is lightning-check, and it's literally the "are we sure about this tho?" command of Core Lightning. no cap.

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🌸 NAME

check — the command for verifying parameters 🎀 (yes, that's its whole job and it does it fabulously)

✨ SYNOPSIS

check command_to_check

🦋 DESCRIPTION

The check RPC command verifies another command without actually making any changes. it's the "try it on in the dressing room but don't buy it" of RPC calls 💅

This is guaranteed to be safe, and it will do all the checks up to the point where something in the system would need to be altered — like checking that channels are in the right state, peers are connected, etc. it goes right up to the line and then respectfully does not cross it 🫶

But — and this is the part where you need to listen, bestie — it does not guarantee successful execution of the command in all cases. for example, a call to lightning-getroute(7) may still fail to find a route even if checking the parameters succeeds. so like, the vibe check passed but the actual route hunt is a whole separate situation 😭

Here's the argument:

• command_to_check (string) — the name of the relevant command. that's it. that's the whole input 👑

🎀 RETURN VALUE

On success, an object is returned, containing:

• command_to_check (string) — the command_to_check argument, just handed right back to you like "yep, I checked the thing you asked me to check" ⭐

👑 AUTHOR

Mark Beckwith wythe@intrig.com and Rusty Russell rusty@rustcorp.com.au are mainly responsible. icons, honestly 🫡

🌈 RESOURCES

Main web site: https://github.com/ElementsProject/lightning — go be nosy 🔥

💖 EXAMPLES

Example 1

Request:

$ lightning-cli check -k "command_to_check"="sendpay" "route"='[{"amount_msat": 1011, "id": "nodeid030303030303030303030303030303030303030303030303030303030303", "delay": 20, "channel": "123x1x1"}, {"amount_msat": 1000, "id": "nodeid040404040404040404040404040404040404040404040404040404040404", "delay": 10, "channel": "130x1x1"}]' "payment_hash"="0000000000000000000000000000000000000000000000000000000000000000"

{
  "id": "example:check#1",
  "method": "check",
  "params": {
    "command_to_check": "sendpay",
    "route": [
      {
        "amount_msat": 1011,
        "id": "nodeid030303030303030303030303030303030303030303030303030303030303",
        "delay": 20,
        "channel": "123x1x1"
      },
      {
        "amount_msat": 1000,
        "id": "nodeid040404040404040404040404040404040404040404040404040404040404",
        "delay": 10,
        "channel": "130x1x1"
      }
    ],
    "payment_hash": "0000000000000000000000000000000000000000000000000000000000000000"
  }
}

Response:

{
  "command_to_check": "sendpay"
}

Example 2

Request:

$ lightning-cli check -k "command_to_check"="dev" "subcommand"="slowcmd" "msec"=1000

{
  "id": "example:check#2",
  "method": "check",
  "params": {
    "command_to_check": "dev",
    "subcommand": "slowcmd",
    "msec": 1000
  }
}

Response:

{
  "command_to_check": "dev"
}

Example 3

Request:

$ lightning-cli check -k "command_to_check"="recover" "hsmsecret"="6c696768746e696e672d31000000000000000000000000000000000000000000"

{
  "id": "example:check#3",
  "method": "check",
  "params": {
    "command_to_check": "recover",
    "hsmsecret": "6c696768746e696e672d31000000000000000000000000000000000000000000"
  }
}

Response:

{
  "command_to_check": "recover"
}

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lowkey the whole point: check lets you peek at whether a command would pass its checks, without touching a single thing in your node. safe, iconic, no notes 💅✨

k that's the page!! mwah 🫶 this was brought to you by Core Lightning v26.06.9 — she's serving documentation realness, periodt 🎀💖