exchangerebel

ExchangeRebel — Pay-Per-Call APIs for AI Agents

A portable Agent Plugins v1 package for Hermes Agent. One install gives
Hermes a bundled workflow skill plus a connection to ExchangeRebel's
remote MCP server: a fleet of pay-per-call data and utility APIs for AI
agents — no accounts, no API keys, no subscriptions. The agent calls,
gets the price up front, pays per call, and receives the answer.

Motto: No harm. Nothing illegal.

What this package contains

hermes-plugin-exchangerebel/
├── plugin.json          # Portable Agent Plugins v1 manifest
├── mcp.json             # The remote MCP server declaration
├── skills/
│   └── exchangerebel/
│       ├── SKILL.md                 # The workflow skill (browse → free call → paid call)
│       └── references/
│           └── counts-and-prices.md # Verified fleet counts and prices, with sources
├── LICENSE              # MIT
└── README.md            # This file — renders on the catalog plugin page

There is no code in this package: no Python, no JavaScript, no binary,
nothing that executes locally and nothing that self-updates. The package
is a manifest, one skill, and one MCP server declaration pointing at a
hosted endpoint.

Install

From the Hermes plugin catalog (once listed):

hermes plugins install exchangerebel
hermes plugins enable exchangerebel

Directly from this repository (unreviewed-source warning applies):

hermes plugins install DataRebelHQ/hermes-plugin-exchangerebel --no-enable
hermes plugins enable exchangerebel

Portable packages are disabled by default after install; the enable
step is what turns the skill and the MCP connection on. Start a new
session after enabling. Requires Hermes 0.22.0 or later (the
Streamable HTTP portable MCP support and the per-server trust
declaration this package uses predate that release line; the current
release at submission time is 0.23.0).

Connect

MCP endpoint (POST, Streamable HTTP): https://exchangerebel.com/mcp
Full machine-readable catalog (every paid operation with its price):
https://exchangerebel.com/openapi.json
Agent discovery file: https://exchangerebel.com/agents.json

The MCP tools/list call is the free catalog: 344 tools as stated
in agents.json — 203 paid via the x402 MCP transport, plus 141 free
tools. Separately, the OpenAPI file declares 241 paid operations,
and agents.json lists 71 toll services. Every figure in this
README was verified from those two live files on 2026-11-09; the
derivation is in skills/exchangerebel/references/counts-and-prices.md.

How payment works

All paid operations use x402 on Solana:

Call a paid operation without payment — you receive a 402 challenge
(SOL recipient + USDC token account + a fresh memo).
Pay with the memo attached via the Solana Memo program.
Retry with the X-Payment-Tx header and the toll_memo query
parameter.

Challenges are dual-version: the PAYMENT-REQUIRED header carries the
x402 v2 PaymentRequired object, and the response body carries the same
challenge in x402 v1 form for compatibility. Settlement is in SOL or
USDC on Solana. You only pay for delivered answers — services with
preflight endpoints validate the request free, before payment.

This package declares the MCP server trust: untrusted in
plugin.json, so Hermes asks you to approve every call that is not
annotated read-only — paid calls never happen silently, and in
unattended runs they fail closed. Hermes v0.23.0 also supports price
tags and spend limits on paid MCP tools; every operation's price is
declared in the OpenAPI file so the host can tag and cap spend before
any call is made.

Prices

Pay per call, USD, taken verbatim from the live OpenAPI file:

Range across all paid operations: $0.002–$50.00 per call
Most operations: $0.005–$0.05 per call
Premium judged verification runs (Agent Data Core Arena):
$10 / $25 / $50 flat
Unless a summary says otherwise, prices are per call — exceptions:
RPC is per 1,000-request block, Telegram provisioning is per
bot-month, transcription is per minute of audio.
Free: every service's catalog / health endpoints, preflight twins,
and the MCP tools/list catalog.

What is in the fleet

Categories drawn from the live catalog: market and crypto data, SEC
filings / fundamentals / Form 4 / 13F, ETF distributions, funding
rates, prediction markets, macro and civic data (BLS, FRED, Congress,
Census, FEC), CourtListener records, EMA medicines, NADAC facts,
recalls, trademark watch, company snapshots and enrichment, news
(GDELT), weather, Wikipedia answers, books, jobs, web rendering and
screenshots, accessibility scans, audio transcription, LLM inference,
developer utilities — and a family of agent-infrastructure
verification services (reputation, readiness, manifest-claim audits,
injection scanning, settlement and receipt verification, and more)
built for agents checking other agents. The bundled skill walks the
agent through the fleet: browse the free catalog, run a free call,
then complete a paid call end to end.

Disclosures — read before installing (catalog rule 13)

Risky behaviour, stated plainly:

Network calls to a third-party service. Enabling this package
connects Hermes to https://exchangerebel.com/mcp, a remote MCP
server run by the operator of ExchangeRebel. Tool calls send the
call's arguments to that server over HTTPS and return its answers.
No other host is contacted by this package.
Paid calls spend real money. 203 of the server's tools are paid.
A paid call that you approve settles in SOL or USDC on Solana via
x402, from the wallet/payment route you use with Hermes. Prices are
$0.002–$50.00 per call (most $0.005–$0.05; the $10/$25/$50 Arena
verification runs are the only calls above $5). The bundled skill
instructs the agent to state the price in dollars before a paid
call and to never pay twice for the same call.
Approval gating. The package sets the server's trust to
untrusted: every non-read-only call asks you first (Once / Session
/ Always, per tool), and fails closed where nobody can answer. You
can widen or narrow this in your own config.yaml; the package
itself never widens it.
No local code, no shell commands, no background processes. The
package ships no executable code and runs nothing locally. It opens
no local ports.
No credentials. This package collects, stores, and reads no
credentials, API keys, or files — mcp.json contains only the
server URL, and no environment variables are required or forwarded.
Payment credentials live in your own Hermes payment setup, never in
this package.
No telemetry. Nothing in this package reports usage anywhere.
The remote server sees the tool calls you make to it, as any API
does.
No self-updating. This package never fetches or replaces its own
files. Updates arrive only as new commits in this repository and,
for catalog installs, only through a reviewed SHA-bump PR.
Funds. ExchangeRebel never holds, custodies, routes, or escrows
funds (per its own agents.json disclaimer) — payments settle
agent-to-service on Solana.

Publisher

ExchangeRebel, run by the operator.
Site: https://exchangerebel.com
Contact (from the live OpenAPI file): sound.money.investing@gmail.com

Licence

MIT — see LICENSE. The licence covers this package (manifest, skill,
and documentation). The remote services it connects to are provided
under their own terms as published on exchangerebel.com.

README from the reviewed commit e5f0ca3; it updates when the author re-pins.