stellar

extending yourself with a new reusable skill by interviewing the user

analyzing a change to determine what tests are needed and adding them to the test suite

modifying build configuration to enable/disable variants, switch compilers or flags, or otherwise prepare for a build

reviewing a change for semantic correctness, simplicity, design consistency, and completeness

reviewing a git diff for small localized coding mistakes that can be fixed without high-level understanding

how to run make correctly to get a good build, and otherwise understand the build system

running tests at various levels from smoke tests to full suite to randomized tests

comprehensive validation of a change to ensure it is correct and ready for a pull request

Agentic and machine-to-machine payments on Stellar. Covers x402 (HTTP 402 paid APIs via OZ Channels facilitator, fee-sponsored clients) and MPP (Machine Payments Protocol) in both Charge mode (per-request Soroban SAC) and Channel mode (off-chain commits, high-frequency). Defaults to USDC (SEP-41 SAC) on `stellar:testnet`/`stellar:pubnet` (CAIP-2). Use when selling a paid API to AI agents, building an x402 client, or designing a payment-channel architecture for high-frequency agent traffic.

Stellar standards, ecosystem, and reference. Covers SEPs (Stellar Ecosystem Proposals), CAPs (Core Advancement Proposals), and a quick map for picking the right standard for wallets, anchors, payments, deposits/withdrawals, federation, deep links, and KYC. Also bundles ecosystem references (DeFi protocols, dev tools, wallets, infra, community projects) and curated documentation links. Use when you need to know which SEP applies, or want a starting point for ecosystem integrations and official docs.

Soroban smart contract development on Stellar (Rust SDK). Covers project setup, contract structure, storage types, authorization, cross-contract calls, events, error handling, testing (unit, integration, fuzz, property, mutation, fork, differential), security patterns and vulnerability classes, advanced architecture patterns (upgrades, factories, governance, DeFi primitives), and common pitfalls. Use when writing, testing, securing, or shipping Soroban contracts.

Stellar Assets (classic) + trustlines + Stellar Asset Contract (SAC) bridge to Soroban. Covers asset issuance, distribution, authorization flags, clawback, regulated assets, trustline management, and the SAC interop layer that exposes classic assets as Soroban tokens. Use when tokenizing real-world assets, issuing stablecoins, managing trustlines, or bridging classic assets to Soroban contracts.

Stellar dApp / frontend development. Covers the JavaScript stellar-sdk (browser + Node.js), Freighter wallet, Stellar Wallets Kit (multi-wallet), Wallet Standard, smart accounts with passkeys, transaction building / signing / submission, Soroban contract invocation from the client, simulation, and error handling. Use when building a React/Next.js/Node.js app that talks to Stellar or Soroban.

Querying Stellar chain data via Stellar RPC (preferred) and Horizon (legacy). Covers RPC JSON-RPC methods, Horizon REST endpoints, streaming, pagination, historical queries, Hubble/Galexie for deep history, and the RPC/Horizon migration story. Use when reading balances, transactions, operations, ledgers, contract events, or building any indexer/analytics workflow.

Zero-knowledge cryptography and privacy patterns on Stellar/Soroban. Covers Groth16 verification, BLS12-381 (CAP-0059, available), BN254 + Poseidon host functions (CAP-0074/0075, status-sensitive), Noir / RISC Zero integration, privacy pools, confidential tokens, Merkle tree commitments, and status-sensitive guidance for protocol/SDK readiness. Use when building privacy-preserving applications or ZK-verifier contracts on Stellar.

Commit a logical unit of work with a descriptive message. Invoke after completing a meaningful chunk (component created, store wired, tests passing) to maintain small, reviewable commits.

Guide for building React components using @stellar/design-system and project SCSS conventions. Invoke when creating new components or reviewing component code.

Bridge Figma MCP output to Stellar Lab code conventions. Invoke after calling get_design_context to translate Figma's reference code into project-appropriate components, classes, and patterns.

Correct mental models for React re-renders and memoization. Use this skill when writing, reviewing, or optimizing React components to avoid common misconceptions about performance. Debunks the myth that "props cause re-renders" and teaches when memoization actually helps.

Reference for the two Zustand store patterns in Stellar Lab — main store (querystring) and transaction flow store (sessionStorage). Invoke when creating store slices, debugging hydration, or deciding where state belongs.

Run e2e and unit tests related to files changed on the current branch. Use after making code changes to verify nothing is broken.

Verification, build, test, and Docker checks for the x402-stellar monorepo. Use before committing, after rebasing, when modifying packages, or when asked to verify the project works.

Project context for the x402-stellar monorepo. Use this to understand what the project does, how it's structured, and how the pieces fit together. Load this first when working on any part of the codebase.

Work on Stellar Core Advancement Proposals in core/. Use when editing CAP documents, checking CAP status fields, or syncing a CAP preamble Status with the corresponding entry in core/README.md.

Comprehensive best practices for the Freighter browser extension. Covers code style, architecture, security, testing, performance, error handling, i18n, messaging, git workflow, dependencies, and anti-patterns. Use when writing new features, reviewing PRs, adding message handlers, working with Redux, modifying content scripts, handling keys, building transactions, or any development work in the freighter extension repo. Triggers on any task touching the freighter codebase.

Use when verifying the full solution works end-to-end — after refactoring, before PRs, or after dependency upgrades. Runs quality pipeline, validates example scripts, and executes live Stellar testnet demos for both charge and channel payment modes.

Audit backend code for security vulnerabilities — DoS vectors, query performance, connection pool exhaustion, injection, missing rate limits, and resource exhaustion