PriorSeal — Claude Code MCP server: bounded agent authorization
Ties a user-signed authorization to one EVM or Solana transaction and returns a portable receipt a third party can check on its own.
claude mcp add --transport http priorseal https://priorseal.xyz/mcpWhat PriorSeal does
PriorSeal sits next to whatever builds and submits your transactions. It never holds wallet keys and never moves funds. An agent proposes an action, the user signs a single-use authorization with an expiry, the server accepts it before execution, then watches the transaction through a configured RPC and compares the supported fields against the signed intent. What comes out is a signed receipt.
Authorizations come as EIP-712, ERC-1271 or Solana Ed25519 messages. Production deployments need an independent pre-execution proof mode — an RFC 3161 timestamp, a witness quorum, or an EVM anchor. The default issuer mode only records that the issuer accepted the authorization. Execution observation needs its own RPC endpoint for the chain in question; Hyperliquid spot orders go through the public Info API instead.
The free MCP surface covers discovery and a purchase handoff. It cannot produce a paid bundle or a Fresh Evidence Check. Paying for an evidence export gives the agent no authority over a customer transaction. Live pricing and enabled rails come from GET /v1/capabilities.
What it helps with
- show which principal authorized an exact contract call
- match a signed intent against observed execution
- hand a reviewer a portable receipt instead of a bare tx hash
- cap an agent's authority to one action and a time window
- compare Solana transaction fields with what the user approved
Example prompts for the agent
- Prepare the transaction and get a bounded authorization through PriorSeal
- Verify the PriorSeal receipt for this transaction
- Call PriorSeal and show what was authorized before execution
How to install PriorSeal
Platform CLI: remote server
claude mcp add --transport http priorseal https://priorseal.xyz/mcpPlatform CLI: remote server
codex mcp add priorseal --url https://priorseal.xyz/mcpConfig file
{
"mcpServers": {
"priorseal": {
"url": "https://priorseal.xyz/mcp"
}
}
}Config file
{
"servers": {
"priorseal": {
"type": "http",
"url": "https://priorseal.xyz/mcp"
}
}
}Platform CLI: remote server
gemini mcp add -t http priorseal https://priorseal.xyz/mcpStep by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about PriorSeal
How do I install PriorSeal in Claude Code?
Run claude mcp add --transport http priorseal https://priorseal.xyz/mcp.
What does PriorSeal do?
It links a principal-signed authorization to a specific EVM or Solana execution and issues a receipt that another party can verify independently.
What does PriorSeal need to work?
Execution observation requires a configured RPC endpoint for that chain. Production also requires an independent pre-execution proof mode rather than the default issuer mode.
