icskills

Guides use of the icp command-line tool for building and deploying Internet Computer applications. Covers project configuration (icp.yaml), recipes, environments, canister lifecycle, identity management, and bundling a project into a self-contained .icp package (icp project bundle). Use when building, deploying, or managing any IC project. Use when the user mentions icp, dfx, canister deployment, local network, project setup, or bundling/packaging an app as an .icp file. Do NOT use for canister-level programming patterns like access control, inter-canister calls, or stable memory — use domain-specific skills instead.

Deploys a built Internet Computer project to a user's cloud engine (an OpenCloud engine): verify the icp CLI, link the console identity with `icp identity link web` (origin defaults to https://opencloud.org; a delegation handoff covers sandboxes whose 127.0.0.1 callback the browser cannot reach), run `icp deploy` against the engine's subnet, tag canisters with `__META_*` env vars for a named console app with labelled canisters and icon, and bake version metadata (service:git:sha, service:version) into the wasm. Also covers a funded proxy canister for cross-subnet cycle-bearing calls (exchange-rate, threshold ECDSA/Schnorr, vetKD). Use when shipping to a cloud engine; on mention of OpenCloud, an engine subnet id, or linking the icp CLI to an engine console; when sign-in never completes from a sandboxed agent; when naming, adding an icon, or recording the deployed version/git commit of a console app. Do NOT use for a general mainnet deploy with no engine or subnet (use icp-cli) or for writing canister logic.

Manage cycles and canister lifecycle. Covers cycle balance checks, top-ups, freezing thresholds, canister creation, and ICP-to-cycles conversion via the CMC. Use when working with cycles, canister funding, freezing threshold, frozen canister, out of cycles, top-up, canister creation, or cycle balance. Do NOT use for wallet-to-dApp integration or ICRC signer flows — use wallet-integration instead.

Manage Motoko projects with the mops CLI — toolchain pinning, dependency management, type-checking, building, and linting. Use when working with mops.toml, mops.lock, running mops commands, adding/removing packages, pinning moc or lintoko versions, checking or building canisters, configuring moc flags, or setting up a new Motoko project.

Improve an existing skill in the IC Skills repo (skills.internetcomputer.org). Load this skill whenever asked to improve, fix, update, enhance, review, or add content to an existing skill at skills/<skill-name>/SKILL.md — including adding pitfalls, updating canister IDs, fixing code examples, strengthening the description, or updating evals. Do NOT use for creating a brand-new skill (use skill-creator for that). Trigger examples: "the motoko skill is missing a pitfall", "update icp-cli for the new recipe format", "the ckbtc description is weak", "add an eval for the canister-security skill".

Deploy frontend assets to the IC. Covers certified assets, SPA routing with .ic-assets.json5, content encoding, and programmatic uploads. Use when hosting a frontend, deploying static files, or setting up SPA routing on IC. Do NOT use for canister-level code patterns or custom domain setup — use custom-domains instead.

Serve cryptographically verified responses from query calls using Merkle trees and subnet BLS signatures. Covers certified data API, RbTree/CertTree construction, witness generation, and frontend certificate validation. Use when query responses need verification, certified data, or response authenticity proofs.

Register and manage custom domains for IC canisters via the HTTP gateway custom domain service. Covers DNS record configuration (CNAME, TXT, ACME challenge), the .well-known/ic-domains file, domain registration/validation/update/deletion via the REST API, TLS certificate provisioning, and HttpAgent host configuration. Use when the user wants to serve a canister under a custom domain, configure DNS for IC, register a domain with boundary nodes, troubleshoot custom domain issues, or update/remove a custom domain. Do NOT use for general frontend hosting or asset canister configuration without custom domains — use asset-canister instead.

Integrate Internet Identity authentication. Covers passkey and OpenID sign-in flows, delegation handling, and principal-per-app isolation. Use when adding sign-in, login, auth, passkeys, or Internet Identity to a frontend or canister. Do NOT use for wallet integration or ICRC signer flows — use wallet-integration instead.

Scaffold and build a complete Caffeine app (caffeine.ai) from scratch — the project layout, the caffeine.toml workspace + canister manifests, the mops.toml for the single Motoko `backend` canister, the React/Vite frontend, and the caffeine CLI build loop (auth login, doctor, install, check --fix, preview --build). Use whenever the user wants to create, scaffold, set up, or build a Caffeine app or a caffeine.ai project, asks about caffeine.toml or mops.toml structure, or needs the caffeine CLI workflow — even if they do not say the words 'from scratch'. Always pair it with the `motoko` skill for the backend code. Do NOT use it for Motoko language syntax or compiler errors (use the `motoko` skill), and do NOT use it for generic Internet Computer / dfx / icp deployment (use the `icp-cli` skill).

Lets an AI agent or CLI session sign in to Internet Identity and act as a user's app-specific principal (e.g. for oisy.com or nns.ic0.app) via `icp identity link web`. Use when the user asks an agent to log in to an II-powered app, obtain a delegation, or make authorized canister calls on their behalf. Do NOT use for adding II sign-in to a frontend — use the internet-identity skill instead.

One-time installer that makes a Claude Code project keep its Internet Computer skills up to date automatically. Sets up a SessionStart hook plus a sync script so .claude/skills/ always mirrors the latest skills published at skills.internetcomputer.org. Use when a user wants to install, bootstrap, or enable "always-latest" Internet Computer / IC / ICP / Motoko skills in a project, or pastes the link to this skill. This is a one-time setup action, not ongoing IC knowledge — after it runs, the installed hook keeps skills current on every session. Do NOT use for IC coding questions themselves — this only configures auto-updating skills.

Create new skills, modify and improve existing skills, and measure skill performance. Use when users want to create a skill from scratch, edit, or optimize an existing skill, run evals to test a skill, benchmark skill performance with variance analysis, or optimize a skill's description for better triggering accuracy.

Enhanced multi-step migration for Motoko actors using a migrations/ directory and --enhanced-migration flag. Use when upgrading canister state across multiple deployments, writing migration files, changing actor field types, or managing a migration chain. For a single one-shot migration, use migrating-motoko instead.

Inline actor migration for Motoko canisters using `(with migration = ...)` syntax. Use when upgrading canister state, renaming fields, changing field types, or restructuring actor state without the --enhanced-migration flag. For multi-step migration chains, use migrating-motoko-enhanced instead.

Motoko language pitfalls, modern syntax, and architecture patterns for the Internet Computer. Covers persistent actors, stable types, mo:core standard library, dot notation, mixins, and common compilation errors. Use when writing Motoko canister code, fixing Motoko compiler errors, or generating Motoko actors. Do NOT use for deployment, icp.yaml, or CLI commands.

IC-specific security patterns for canister development in Motoko and Rust. Covers access control, anonymous principal rejection, reentrancy prevention (CallerGuard pattern), async safety (saga pattern), callback trap handling, cycle drain protection, and safe upgrade patterns. Use when writing or modifying any canister that modifies state, handles tokens, makes inter-canister calls, or implements access control.

ICP / DFINITY visual design system v2: tokens, color, typography, layout, components, accessibility for DFINITY and Internet Computer surfaces. Pairs with icp-brand-voice. Use when building or reviewing visual surfaces (NNS, ICP.app, Internet Identity, dashboards, the main website, developer docs, marketing). Enforces the system that ships on internetcomputer.org: three faces (Newsreader, Inter, JetBrains Mono), single rust accent, light editorial parchment as the default theme with an opt-in dark theme for product surfaces that need it, sentence case, italic for asides only, no em-dashes (U+2014), tamperproof spelled as one word. Triggers: ICP design, DFINITY design, brand tokens, design review ICP, color palette, typography ICP, NNS redesign, light or dark mode ICP. OISY, Caffeine, and ecosystem products with their own brand are out of scope.

ICP / DFINITY positioning, voice, and vocabulary v2 for surfaces under the DFINITY or Internet Computer (ICP) mark. Pairs with icp-brand-design (colors, typography, components). Use when writing or reviewing copy, UI strings, headlines, hero lines, buttons, errors, empty states, release notes, blog posts, marketing pages, developer docs, social posts, decks. Enforces the calm, factual, plain voice (no hyperbole, no em-dashes, no emoji), the locked positioning ("Sovereign frontier cloud / Scaling AI that builds"), the four voice attributes (Factual, Plain, Calm, Sovereign by math), and the strict ban on bare "onchain" and "on-chain" as nouns, attributes, or selling points. Triggers, ICP voice, DFINITY voice, brand voice, is this on brand copy, vocabulary check, tagline review, headline review, ICP positioning, how should we describe ICP, write a headline. Products with their own voice (OISY, Caffeine, future ecosystem products with their own verbal systems) are out of scope.

Accept, send, and manage ckBTC (chain-key Bitcoin). Covers BTC deposit flow via minter, ckBTC transfers, withdrawal to BTC, subaccount derivation, and UTXO management. Use when integrating Bitcoin, ckBTC, BTC deposits, or BTC withdrawals in a canister. Do NOT use for plain token transfers without BTC minting/withdrawal — use icrc-ledger instead.

Call Ethereum and EVM chains from IC canisters (Rust) via the EVM RPC canister using the evm_rpc_client crate. Covers typed API calls, raw JSON-RPC, multi-provider consensus, ERC-20 reads, and sending pre-signed transactions. Use when calling Ethereum, Arbitrum, Base, Optimism, or any EVM chain from a Rust canister. Do NOT use for generic HTTPS calls to non-EVM APIs — use https-outcalls instead.

Deploy and interact with ICRC-1/ICRC-2 token ledgers (ICP, ckBTC, ckETH). Covers transfers, balances, approve/transferFrom allowances, fee handling, and ledger deployment. Use when working with ICP transfers, token transfers, balances, ICRC-1, ICRC-2, approve, allowance, or any fungible token on IC. Do NOT use for ckBTC minting or BTC deposit/withdrawal flows — use ckbtc instead.

Design and deploy multi-canister dapps. Covers inter-canister calls, canister factory pattern, async messaging pitfalls, bounded vs unbounded wait, and 2MB payload limits. Use when splitting an app across canisters, making inter-canister or cross-canister calls, or designing canister-to-canister communication. Do NOT use for single-canister apps.

Persist canister state across upgrades. Covers StableBTreeMap and MemoryManager in Rust, persistent actor in Motoko, and upgrade hook patterns. Use when dealing with canister upgrades, data persistence, data lost after upgrade, stable storage, StableBTreeMap, pre_upgrade traps, or heap vs stable memory. Do NOT use for inter-canister calls or access control — use multi-canister or canister-security instead.

Integrate wallets with IC dApps using ICRC signer standards (ICRC-21/25/27/29/49). Covers the popup-based signer model, consent messages, permission lifecycle, and transaction approval flows. Implementation uses @dfinity/oisy-wallet-signer. Do NOT use for Internet Identity login, delegation-based auth (ICRC-34/46), or threshold signing (chain-key). Use when the developer mentions wallet integration, OISY, oisy-wallet-signer, wallet signer, relying party, consent messages, wallet popup, or transaction approval.

Display a human-readable summary of a canister's interface given its mainnet canister ID or a human-readable name. Like --help but for canisters. Only for mainnet canisters — for local canisters, read the generated .did file in your project directly.

Make HTTPS requests from canisters to external web APIs. Covers transform functions for consensus, cycle cost management, response size limits, and idempotency patterns. Use when a canister needs to call an external API, fetch data from the web, or make HTTP requests. Do NOT use for EVM/Ethereum calls — use evm-rpc instead.

Configure and launch an SNS DAO to decentralize a dapp. Covers token economics, governance parameters, testflight validation, NNS proposal submission, and decentralization swap. Use when launching an SNS, configuring tokenomics, or setting up DAO governance for a dapp. Do NOT use for NNS governance or general canister management.

Implement on-chain encryption using vetKeys (verifiable encrypted threshold key derivation). Covers key derivation, IBE encryption/decryption, transport keys, and access control. Use when adding encryption, decryption, on-chain privacy, vetKeys, or identity-based encryption to a canister. Do NOT use for authentication — use internet-identity instead.

Query the public REST APIs that power dashboard.internetcomputer.org. Covers canister metadata, ICRC ledger data, SNS data, ICP ledger, and network metrics with cursor-based pagination. Use when fetching canister info, token data, SNS proposals, or network stats via HTTP from off-chain code. No canister deployment or cycles needed.