examples(python): add langchain-krewe-inference-chatbot

README.md

@@ -183,6 +183,7 @@ agentkit/
 │       ├── langchain-cdp-smart-wallet-chatbot/
 │       ├── langchain-cdp-solana-chatbot/
 │       ├── langchain-eth-account-chatbot/
+│       ├── langchain-krewe-inference-chatbot/
 │       ├── langchain-nillion-secretvault-chatbot/
 │       ├── langchain-twitter-chatbot/
 │       ├── openai-agents-sdk-cdp-chatbot/

python/examples/langchain-krewe-inference-chatbot/.env.local

@@ -0,0 +1,22 @@
+# Required
+CDP_API_KEY_ID=
+CDP_API_KEY_SECRET=
+CDP_WALLET_SECRET=
+OPENAI_API_KEY=
+
+# Optional — krewe is mainnet-only today. Set to base-sepolia if you've
+# pointed krewe at a sepolia orchestrator (see KREWE_PREDICT_URL below).
+NETWORK_ID=base-mainnet
+
+# Optional — override the krewe orchestrator URL (e.g. for self-hosted
+# orchestrators or staging). Defaults to the production Railway orchestrator.
+KREWE_PREDICT_URL=https://krewe-orchestrator-production.up.railway.app/v2/predict
+
+# Optional — hard ceiling on USDC per call. Defaults to $0.10. Pricing today:
+# $0.005 text.structure, $0.01 text.embed, $0.02 web.scrape, $0.05 text.complete.
+KREWE_MAX_PAYMENT_USDC=0.10
+
+# Optional account knobs (inherited from the CDP template)
+ADDRESS=
+IDEMPOTENCY_KEY=
+RPC_URL=

python/examples/langchain-krewe-inference-chatbot/Makefile

@@ -0,0 +1,29 @@
+ifneq (,$(wildcard ./.env))
+	include .env
+endif
+
+export
+
+.PHONY: install
+install:
+	uv sync
+
+.PHONY: run
+run:
+	uv run chatbot.py
+
+.PHONY: format
+format:
+	uv run ruff format .
+
+.PHONY: format-check
+format-check:
+	uv run ruff format . --check
+
+.PHONY: lint
+lint:
+	uv run ruff check .
+
+.PHONY: lint-fix
+lint-fix:
+	uv run ruff check . --fix

python/examples/langchain-krewe-inference-chatbot/README.md

@@ -0,0 +1,101 @@
+# krewe Inference + AgentKit + LangChain — Python Chatbot
+
+This example shows how a Python LangChain agent can call **[krewe](https://www.krewe.world)** — a decentralized AI inference network on Base mainnet — using AgentKit's built-in `x402_action_provider`. Each inference call is paid per-request in USDC via the [x402 protocol](https://x402.org); no API keys or pre-paid quotas required.
+
+The agent has a CDP-managed Base wallet and four inference tools through krewe:
+
+| `kind`           | Cost   | What it does                                                          |
+| ---------------- | ------ | --------------------------------------------------------------------- |
+| `text.structure` | $0.005 | Regex/JSON extraction from unstructured text                          |
+| `text.embed`     | $0.01  | Sentence embeddings via a small quantized model                       |
+| `web.scrape`     | $0.02  | Fetch + clean a URL payload                                           |
+| `text.complete`  | $0.05  | Small-language-model completion (greedy decode, server-pinned model)  |
+
+Every USDC paid through this example flows directly back to the miners that answered the job — krewe's orchestrator sweeps payments hourly, swaps them for `$KREW` on Uniswap V4, and deposits the proceeds into the registry's reward pool.
+
+This is the Python sibling to the [TypeScript example](../../../typescript/examples/langchain-krewe-inference-chatbot/) — same orchestrator, same pricing, same auth flow, native Python idioms.
+
+## Prompts to try
+
+- `"Extract every email and date from this text: 'RSVP to hi@krewe.world by 2026-05-17 or call us 2026-05-20.'"`
+- `"Embed this sentence: 'Decentralized AI inference on Base'."`
+- `"Scrape https://www.krewe.world and tell me what the project does."`
+- `"Use krewe's text.complete to write a one-sentence summary of x402."`
+
+## Prerequisites
+
+- **Python 3.10+** — verify with `python3 --version`. Install via [pyenv](https://github.com/pyenv/pyenv) if needed.
+- **[uv](https://docs.astral.sh/uv/)** — the package manager this example uses.
+- API keys:
+  - **CDP API key** — https://portal.cdp.coinbase.com/access/api
+  - **CDP wallet secret** — https://portal.cdp.coinbase.com/products/wallet-api
+  - **OpenAI API key** — https://platform.openai.com/docs/quickstart#create-and-export-an-api-key
+
+Rename `.env.local` to `.env` and fill in:
+
+```bash
+CDP_API_KEY_ID=...
+CDP_API_KEY_SECRET=...
+CDP_WALLET_SECRET=...
+OPENAI_API_KEY=...
+
+NETWORK_ID=base-mainnet                       # krewe is mainnet-only today
+KREWE_PREDICT_URL=https://krewe-orchestrator-production.up.railway.app/v2/predict
+KREWE_MAX_PAYMENT_USDC=0.10                   # safety cap per call
+```
+
+### Funding the agent
+
+The agent's CDP wallet needs **USDC on Base mainnet** to pay for inference. The cheapest job (`text.structure`) costs $0.005, so $1 funds 200 calls. Send USDC to the wallet address printed at startup.
+
+> Note: krewe's *production* orchestrator runs only on Base mainnet today. The `NETWORK_ID=base-sepolia` path works against a self-hosted orchestrator.
+
+## Running the example
+
+From the repository root:
+
+```bash
+cd python/examples/langchain-krewe-inference-chatbot
+make install     # uv sync — installs deps + the in-tree coinbase-agentkit
+make run         # uv run chatbot.py
+```
+
+You'll be prompted for **chat** (interactive prompts) or **auto** (autonomous loop that fires a creative krewe job every 30s).
+
+## How the x402 handshake works under the hood
+
+The flow is invisible to your agent code, but worth knowing:
+
+1. Agent calls `https://krewe-orchestrator-production.up.railway.app/v2/predict` with a job body.
+2. Orchestrator returns `402 Payment Required` with a signed EIP-3009 challenge specifying the USDC `value`, `to`, `nonce`, and validity window.
+3. AgentKit's `x402_action_provider` signs the challenge with the CDP wallet (via the x402 facilitator).
+4. Orchestrator verifies the signature, submits `transferWithAuthorization` on the USDC contract, waits for confirmation, then runs the inference job through krewe's miner network.
+5. 2-of-3 byte-equal miner consensus produces the output, which is returned along with the on-chain `paymentTxHash`.
+
+Full protocol writeup: [`docs/x402.md`](https://github.com/krewe-AI/krewe/blob/main/docs/x402.md) in the krewe repo.
+
+## Without AgentKit — direct krewe Python SDK
+
+If you only need to call krewe (not the full AgentKit stack), the standalone [`krewe-x402`](https://pypi.org/project/krewe-x402/) package is simpler — no CDP wallet provider needed, just an `eth_account.Account`:
+
+```python
+from eth_account import Account
+from krewe_x402 import KreweClient
+
+with KreweClient(account=Account.from_key("0x...")) as client:
+    result = client.predict(kind="text.structure",
+                            payload={"text": "Email hi@krewe.world by 2026-05-17"})
+print(result["output"])
+```
+
+## Want a self-hosted orchestrator?
+
+The orchestrator is open-source and small (~2k LOC of TypeScript). See [`SETUP.md`](https://github.com/krewe-AI/krewe/blob/main/SETUP.md) in the krewe repo for the dev path, and [`docs/architecture.md`](https://github.com/krewe-AI/krewe/blob/main/docs/architecture.md) for the network model. Point `KREWE_PREDICT_URL` at your instance and this example works against it unchanged.
+
+## Links
+
+- krewe site: https://www.krewe.world
+- krewe repo: https://github.com/krewe-AI/krewe
+- `$KREW` on Basescan: https://basescan.org/address/0xc411E6deE1F70F57F08714D3bd54b4F36f904B07
+- x402 spec: https://x402.org
+- AgentKit docs: https://docs.cdp.coinbase.com/agentkit/docs/welcome