Fetcher — Filecoin Agent SDK

Agent-native tools for Filecoin Onchain Cloud via Synapse SDK.

🤖 AI Agents  →  👻 Fetcher SDK  →  🌐 Synapse SDK  →  ⛓ Filecoin Onchain Cloud
Claude · GPT    MCP + LangChain    Filecoin official    PDP every hour
LangChain        LlamaIndex · SDK   TypeScript native    Verifiable storage

Packages

Package	Purpose	Tools
@fetcher-fil/core	Core storage API, spending policy, Synapse backend, memory system	All 17
@fetcher-fil/mcp	MCP stdio server for Claude Desktop and MCP clients	17
@fetcher-fil/langchain	LangChain DynamicStructuredTools	17
@fetcher-fil/llamaindex	LlamaIndex FunctionTools	17
@fetcher-fil/sdk	Programmatic Fetcher class	17
@fetcher-fil/testkit	Fake backend and fixtures for tests	—

Quick Start — MCP (Claude Desktop)

{
  "mcpServers": {
    "fetcher": {
      "command": "npx",
      "args": ["@fetcher-fil/mcp"],
      "env": {
        "FILECOIN_PRIVATE_KEY": "0x...",
        "FILECOIN_NETWORK": "calibration",
        "FILECOIN_AGENT_ALLOW_PAID": "true"
      }
    }
  }
}

Your agent gets 17 tools: store_file, retrieve_file, list_files, verify_cid, check_deal, get_proof, prepare_storage, delete_file, get_balance, estimate_cost, get_storage_stats, list_deals, store_memory, retrieve_memory, update_memory, list_memories, delete_memory.

Quick Start — LangChain

import { createFetcherTools } from "@fetcher-fil/langchain";
import { createSynapseBackend } from "@fetcher-fil/core";

const tools = createFetcherTools({
  backend: await createSynapseBackend({ privateKey: "0x..." }),
  spendingPolicy: { allowPaidOperations: true }
});

Quick Start — LlamaIndex

import { createFetcherTools } from "@fetcher-fil/llamaindex";
import { createSynapseBackend } from "@fetcher-fil/core";

const tools = createFetcherTools({
  backend: await createSynapseBackend({ privateKey: "0x..." }),
  spendingPolicy: { allowPaidOperations: true }
});

Quick Start — SDK Direct

import { Fetcher } from "@fetcher-fil/sdk";
import { createSynapseBackend } from "@fetcher-fil/core";

const fetcher = new Fetcher({
  backend: await createSynapseBackend({ privateKey: "0x..." }),
  spendingPolicy: { allowPaidOperations: true }
});

const { cid } = await fetcher.store({ content: "Hello Filecoin", filename: "hello.txt" });
const stats = await fetcher.stats();

await fetcher.memory.store({
  agentId: "my-agent",
  memoryKey: "preferences",
  data: { theme: "dark" }
});

const mem = await fetcher.memory.retrieve({ agentId: "my-agent", memoryKey: "preferences" });

Safety

Paid operations blocked by default. Start on Calibration. Read docs/security.md.

Verify

npm test
npm run build