@three-ws/solana-memo-media-mcp

Read and display image data URIs embedded in Solana SPL Memo instructions. Instead of copying a data:image/...;base64,... memo payload into a browser converter, give an AI assistant the transaction signature and receive the validated image inline.

This is a keyless, read-only stdio MCP server. It never signs, sends, uploads, caches, or modifies chain data.

#Install

claude mcp add solana-memo-media -- npx -y @three-ws/solana-memo-media-mcp

For Cursor, Claude Desktop, or another stdio MCP client:

{
  "mcpServers": {
    "solana-memo-media": {
      "command": "npx",
      "args": ["-y", "@three-ws/solana-memo-media-mcp"]
    }
  }
}

#Tools

Tool	Purpose
`extract_solana_memo_media`	Fetch one legacy, v0, or v1 transaction and return every supported image in its top-level and inner Memo instructions, with signer, slot, and version.
`find_solana_memo_media`	Scan up to 1,000 recent signatures for an address (pageable with `before`). Only signatures whose memo summary holds a data URI are fetched, so a scan costs a handful of RPC calls.
`decode_solana_memo_data_uri`	Decode one already-copied data URI locally. No network call.
`get_solana_memo_media_status`	Show the local policy, recognized memo programs, and RPC failover hosts. No network call.

Recognized memo programs: SPL Memo v1 (Memo1UhkJRfHyvLMcVLMbLJYfW2tfU8G8H4PqvV6v8), SPL Memo v2 (MemoSq4gqABAXKb96qnH8TysNcWxMyWCqXgDLGmfcHr), and the newer program carried by version 1 transactions (Memo4c2pN8afCj432Lb7RMVKi9PbQnnW7ewFFaV3oAH).

#Example

Ask an MCP client: "Show any image embedded in Solana transaction <signature>." It calls extract_solana_memo_media with:

{ "signature": "<base58 Solana transaction signature>" }

The response is a JSON record plus one MCP image content block per asset. The record carries the signature, fee payer, slot, transaction version, and for each asset its MIME type, byte length, SHA-256, and dimensions. The raw data URI is intentionally not echoed into text output.

Use it from your own code:

import { decodeDataUri } from '@three-ws/solana-memo-media-mcp/src/lib/media.js';

const media = decodeDataUri('data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAADUlEQVR42mP8z8BQDwAFgwJ/lwV8YQAAAABJRU5ErkJggg==');
console.log(media.mimeType, media.byteLength, media.dimensions, media.sha256);

Full guide: docs/mcp-solana-memo-media.md.

#Safety and provenance

An SPL Memo is arbitrary signed text. A data URI is only a convention inside that text, not a Solana media standard and not an endorsement by a wallet, explorer, or this package.

Only image/png, image/jpeg, image/webp, and image/gif are accepted.
SVG and all executable or document media are rejected.
Decoded content is capped at 262,144 bytes.
The declared MIME type must match PNG, JPEG, WebP, or GIF file signatures before an image is returned.
The server reports a SHA-256 digest so callers can preserve an exact reference.
Verify the transaction signer, program, and surrounding transaction context independently before trusting what an image means.

#RPC configuration

The server tries SOLANA_RPC_URLS, then SOLANA_RPC_URL, then public Solana mainnet endpoints. You do not need a key for normal use.

Variable	Required	Meaning
`SOLANA_RPC_URLS`	no	Comma-separated ordered JSON-RPC failover endpoints.
`SOLANA_RPC_URL`	no	One primary JSON-RPC endpoint.

#Development

npm test --prefix packages/solana-memo-media-mcp
npx -y @modelcontextprotocol/inspector node packages/solana-memo-media-mcp/src/index.js

License: Apache-2.0.