contract

Contract Skill

Provides Clarity smart contract deployment and interaction on the Stacks blockchain. Deploy contracts from .clar source files, call public functions (with optional post conditions), and call read-only functions to query on-chain state.

• read — Read-only, no wallet required.
• deploy and call — Write operations that broadcast transactions; require an unlocked wallet.

Usage

bun run contract/contract.ts <subcommand> [options]

Subcommands

deploy

Deploy a Clarity smart contract to the Stacks blockchain. Reads the contract source from a .clar file and broadcasts a smart_contract transaction.

bun run contract/contract.ts deploy \
  --source <path-to-file.clar> \
  --name <contract-name> \
  [--fee <fee>]

Options:

• --source (required) — Path to the .clar source file to deploy
• --name (required) — Contract name (lowercase, hyphens allowed, max 128 chars)
• --fee (optional) — Fee preset (low|medium|high) or micro-STX amount; auto-estimated if omitted

Output:

{
  "success": true,
  "txid": "abc123...",
  "contractId": "SP2...deployer.my-contract",
  "network": "mainnet",
  "explorerUrl": "https://explorer.hiro.so/txid/abc123...?chain=mainnet"
}

call

Call a public function on a deployed Stacks smart contract. Signs and broadcasts a contract_call transaction.

bun run contract/contract.ts call \
  --contract <contractId> \
  --function <functionName> \
  --args <json-array> \
  [--post-condition-mode <deny|allow>] \
  [--post-conditions <json-array>] \
  [--fee <fee>]

Options:

• --contract (required) — Full contract ID in ADDRESS.contract-name format
• --function (required) — Public function name to call
• --args (optional) — Function arguments as a JSON array (default: []). Typed objects use {"type":"uint","value":100} format.
• --post-condition-mode (optional) — deny (default) blocks unexpected token transfers; allow permits any
• --post-conditions (optional) — Post conditions as a JSON array (see Notes for format)
• --fee (optional) — Fee preset (low|medium|high) or micro-STX amount; auto-estimated if omitted

Output:

{
  "success": true,
  "txid": "abc123...",
  "contract": "SP2...deployer.my-contract",
  "function": "set-value",
  "args": [42],
  "network": "mainnet",
  "explorerUrl": "https://explorer.hiro.so/txid/abc123...?chain=mainnet"
}

read

Call a read-only function on a deployed Stacks smart contract. Does not broadcast a transaction; no wallet required.

bun run contract/contract.ts read \
  --contract <contractId> \
  --function <functionName> \
  [--args <json-array>] \
  [--sender <address>]

Options:

• --contract (required) — Full contract ID in ADDRESS.contract-name format
• --function (required) — Read-only function name to call
• --args (optional) — Function arguments as a JSON array (default: [])
• --sender (optional) — Stacks address to use as the read-only call sender (uses active wallet address if omitted)

Output:

{
  "contract": "SP2...deployer.my-contract",
  "function": "get-value",
  "okay": true,
  "result": "(ok u42)",
  "network": "mainnet"
}

Arguments

Subcommand	Option	Required	Description
deploy	--source	yes	Path to .clar source file
deploy	--name	yes	Contract name
deploy	--fee	no	Fee preset or micro-STX amount
call	--contract	yes	Full contract ID (ADDRESS.name)
call	--function	yes	Public function name
call	--args	no	JSON array of function arguments
call	--post-condition-mode	no	deny (default) or allow
call	--post-conditions	no	JSON array of post condition objects
call	--fee	no	Fee preset or micro-STX amount
read	--contract	yes	Full contract ID (ADDRESS.name)
read	--function	yes	Read-only function name
read	--args	no	JSON array of function arguments
read	--sender	no	Sender address for the read-only call

Notes

• Contract names must be unique per deployer address. Deploying a contract that already exists will fail.
• Deployment is irreversible — the contract lives on-chain permanently once confirmed.
• Pre-simulate contract calls on stxer.xyz before deploying or calling to catch Clarity errors and estimate fees without spending STX.
• Post condition format: {"type":"stx","principal":"SP2...","conditionCode":"eq","amount":"1000000"} for STX; {"type":"ft","principal":"SP2...","asset":"SP2....my-token","assetName":"my-token","conditionCode":"eq","amount":"100"} for fungible tokens; {"type":"nft","principal":"SP2...","asset":"SP2....my-nft","assetName":"my-nft","tokenId":1} for NFTs — NFT conditions are binary (send/not-send), so conditionCode is not applicable; use "notSend":true to assert the NFT must NOT leave the principal.
• --post-condition-mode allow skips post condition checks entirely — use only when you fully trust the contract logic and have verified the source code.
• Wallet operations require an unlocked wallet (use bun run wallet/wallet.ts unlock --password <password> first).