@bsvkey/inference-mcp
An MCP server that lets any agent buy Claude & Grok inference metered per token,
settled in BSV, through the hosted gateway at inference.bsvkey.com. Zero
dependencies (Node ≥ 18, uses global fetch). It's a thin HTTP client — it never
holds your keys or runs models; every call is billed through the gateway.
Tools: list_models, infer, channel_balance, open_channel, x402_infer, xrp_infer.
Two ways to pay: a prepaid channel (infer, fund once, draw down per token) or
per call via x402 (x402_infer — no channel; the agent pays each request in BSV
with its own key). x402_infer needs a funded WIF (wif arg or BSVKEY_WIF) and the
optional @bsvkey/x402-bsv-client + @bsv/sdk packages (installed with this one).
Pay per call in XRP with xrp_infer: the tool gets a quote in XRP (priced from
the XRP Ledger's own XRP/RLUSD market), signs one XRP Payment for exactly that
locally, and the gateway checks it before broadcasting, waits for validation (a few
seconds), and returns the answer, the settlement tx, and a signed receipt. It needs
a funded XRP seed (xrpSeed arg or BSVKEY_XRP_SEED; create one at
xrp.bsvkey.com/wallet) and the optional xrpl
package (installed with this one; it needs Node 20.19+ or 22.12+). The account
keeps a 1 XRP reserve that can't be spent.
Verifiable metering. Each infer call returns a signed usage receipt, and the
tool auto-verifies it offline (with the optional packages installed): the result
includes receiptVerified and meterVerified (true, false + receiptCheck,
or null). It recovers the broker key (pinned from GET /v1/receipt-key); binds
the receipt to the channel you called (from your API key, not the receipt's
self-report); checks a monotonic sequence (no replay/gap) and running totals within
the funded amount; recomputes the charge from the published rate (you can never
be overcharged); and recomputes the token count from the exact bytes of your
messages and the completion, under the pinned bsvkey-meter/1 tokenizer. So the
channel payment is on-chain and both the meter and the charge are auditable,
without trusting the broker's word.
Four things an unattended client should know:
- Fails closed. If the pinned-key endpoint is unreachable,
receiptVerifiedisnull(unknown), nevertrue— a down pin weakens the check to unknown, not to trusted. - Supply your funded amount. Set
BSVKEY_FUNDED_SATS(or passfundedSats) to the amount you funded on-chain. The receipt's ownfundedSatsis the broker's assertion; when you supply yours, a receipt claiming a different amount is rejected and totals are checked against what you actually paid. - Persist across restarts. Sequence continuity is in-memory by default (a
replay before the first receipt this process sees would be invisible). Set
BSVKEY_RECEIPT_STATEto a file path to persist per-channelseq/totals so replays are caught across restarts. - The receipt is the ledger. The
GET /v1/channels/:idbalance endpoint can lag the signed receipt by ~20s; trust the receipt, treat the endpoint as a cache.
Spec: https://inference.bsvkey.com/usage-receipts.md
Quick start
- Fund a channel once at https://inference.bsvkey.com (BRC-100 wallet, or
load a key in-page). Copy the key it returns:
channelId:channelSecret. - Add the MCP server to your agent host (below), with that key in
BSVKEY_API_KEY. - Ask your agent to run inference — it calls
inferand pays per token.
list_models and open_channel work with no key; infer and channel_balance
need a funded channel key.
Install
Published on npm as @bsvkey/inference-mcp.
Claude Code
claude mcp add bsvkey-inference \
--env BSVKEY_API_KEY=channelId:channelSecret \
-- npx -y @bsvkey/inference-mcp
Claude Desktop / Codex / any MCP host (JSON config)
{
"mcpServers": {
"bsvkey-inference": {
"command": "npx",
"args": ["-y", "@bsvkey/inference-mcp"],
"env": { "BSVKEY_API_KEY": "channelId:channelSecret" }
}
}
}
No npm? Grab the single-file server directly (https://inference.bsvkey.com/mcp/server.js) and use "command": "node", "args": ["server.js"].
Configuration (env)
Errors
A failed tool call returns isError: true with text in one fixed shape, so an
agent can branch on the code without parsing prose:
error: <code> (<http status>): <message> [extra=value, ...]
On a prepaid channel nothing is charged on any error. A successful infer can
still report receiptVerified: false (the signed receipt didn't check out; see
receiptCheck) or null (couldn't check: verifier missing, or the receipt-key
endpoint was down).
Thinking models (claude-sonnet-5, claude-opus-5, claude-opus-5-5,
claude-fable-5-1) bill their hidden reasoning as output, and maxTokens is
raised to at least 1024 for them.
Verify it's wired (no key needed)
printf '%s\n' \
'{"jsonrpc":"2.0","id":1,"method":"initialize","params":{}}' \
'{"jsonrpc":"2.0","id":2,"method":"tools/list","params":{}}' \
'{"jsonrpc":"2.0","id":3,"method":"tools/call","params":{"name":"list_models","arguments":{}}}' \
| node server.js
Marketplace listing blurb
BSV Inference — Pay-per-token Claude & Grok, settled in BSV. Prepay a channel once, then meter every token with no subscription, account, or card. OpenAI- compatible, optional live web search, on-chain settlement. MCP + portable SKILL.md.
Publishing (operator)
- Live on npm under the
@bsvkeyorg (owner:interence). First publish: v1.0.0. - To ship an update: bump
versioninpackage.json, thennpm publish --access public(2FA/security-key prompt applies). - Canonical source: https://github.com/BSVKey/inference-mcp
- To list on a skills marketplace (e.g. bopen.ai), submit
SKILL.md+ this README.