Config is the same across clients — only the file and path differ.
{
"mcpServers": {
"io-github-srotzin-hive-mcp-barter": {
"args": [
"-y",
"npm"
],
"command": "npx"
}
}
}Are you the author?
Add this badge to your README to show your security score and help users find safe servers.
Outbound 402 arbitrage agent — Hive Civilization
Run this in your terminal to verify the server starts. Then let us know if it worked — your result helps other developers.
npx -y 'npm' 2>&1 | head -1 && echo "✓ Server started successfully"
After testing, let us know if it worked:
Five weighted categories — click any category to see the underlying evidence.
Packing does not respect root-level ignore files in workspaces
### Impact `npm pack` ignores root-level `.gitignore` & `.npmignore` file exclusion directives when run in a workspace or with a workspace flag (ie. `--workspaces`, `--workspace=<name>`). Anyone who has run `npm pack` or `npm publish` with workspaces, as of [v7.9.0](https://github.com/npm/cli/releases/tag/v7.9.0) & [v7.13.0](https://github.com/npm/cli/releases/tag/v7.13.0) respectively, may be affected and have published files into the npm registry they did not intend to include. ### Patch - Up
Incorrect Permission Assignment for Critical Resource in NPM
An issue was discovered in an npm 5.7.0 2018-02-21 pre-release (marked as "next: 5.7.0" and therefore automatically installed by an "npm upgrade -g npm" command, and also announced in the vendor's blog without mention of pre-release status). It might allow local users to bypass intended filesystem access restrictions because ownerships of /etc and /usr directories are being changed unexpectedly, related to a "correctMkdir" issue.
Local Privilege Escalation in npm
Affected versions of `npm` use predictable temporary file names during archive unpacking. If an attacker can create a symbolic link at the location of one of these temporary file names, the attacker can arbitrarily write to any file that the user which owns the `npm` process has permission to write to, potentially resulting in local privilege escalation. ## Recommendation Update to version 1.3.3 or later.
npm CLI exposing sensitive information through logs
Versions of the npm CLI prior to 6.14.6 are vulnerable to an information exposure vulnerability through log files. The CLI supports URLs like `<protocol>://[<user>[:<password>]@]<hostname>[:<port>][:][/]<path>`. The password value is not redacted and is printed to stdout and also to any generated log files.
npm Vulnerable to Global node_modules Binary Overwrite
Versions of the npm CLI prior to 6.13.4 are vulnerable to a Global node_modules Binary Overwrite. It fails to prevent existing globally-installed binaries to be overwritten by other package installations. For example, if a package was installed globally and created a `serve` binary, any subsequent installs of packages that also create a `serve` binary would overwrite the first binary. This will not overwrite system binaries but only binaries put into the global node_modules directory. This b
Click any tool to inspect its schema.
Be the first to review
Have you used this server?
Share your experience — it helps other developers decide.
Sign in to write a review.
Others in other
Compress tool outputs, logs, files, and RAG chunks before they reach the LLM. 60-95% fewer tokens, same answers. Library, proxy, MCP server.
Pi Coding Agent extension (CLI-first) — routes bash/read/grep/find/ls through lean-ctx CLI for strong token savings. Optional MCP bridge can register advanced tools.
AI travel agent — 1 smart MCP tool plus 62 compatibility aliases for flights, hotels, ground transport, price alerts. No API keys required.
Research graph MCP for hypotheses, goals, runs, source quality, audits, and generated maps.
MCP Security Weekly
Get CVE alerts and security updates for io.github.srotzin/hive-mcp-barter and similar servers.
Start a conversation
Ask a question, share a tip, or report an issue.
Sign in to join the discussion.
Outbound 402 arbitrage agent — Hive Civilization
Probes 402-enabled MCP endpoints, counter-offers below asking, and settles when the spread clears our resale floor. Pure protocol — no DMs, no spam. Attribution headers on every request.
Council provenance: Ad-hoc, user-promoted 2026-04-27 (Tier A position 1).
hive-mcp-barter is a Model Context Protocol server that runs an outbound arbitrage loop on top of the 402 payment surface. It scans public MCP registries for 402-enabled endpoints, probes them with standard quote requests, and — when target_asking × counter_pct still lands below our resale floor — issues a single-shot, pre-signed counter-offer. The target accepts by broadcasting our pre-signed transaction; there is no haggle, no second round, and no human-readable outreach.
POST /mcpGET /.well-known/mcp.jsonGET /health#C08D23| Tool | Tier | Description |
|---|---|---|
barter_discover | 0 (free) | List 402-enabled MCP endpoints from a public registry (glama, smithery, mcp.so) with last-seen asking prices. |
barter_quote_curve | 0 (free) | Build a demand curve for a target by sending up to 5 probes at descending floor pcts. Returns the reservation-price estimate. |
barter_arbitrage_book | 0 (free) | Today's P&L: probes sent, counters accepted, USDC realized spread. |
| Method | Path | Purpose |
|---|---|---|
POST | /v1/barter/discover | Scan registries for 402 endpoints. |
POST | /v1/barter/probe | Send a 402-style quote request to a target. |
POST | /v1/barter/counter | Build a signed counter-offer at the configured floor pct. |
POST | /v1/barter/settle | Resolve an accepted counter on-chain and book the spread. |
GET | /v1/barter/ledger | Running P&L, attempts, wins, spread. |
GET | /v1/barter/today | Today aggregate (Tier 0, free). |
GET | /health | Service health. |
{
"x402_version": 1,
"intent": "counter_offer",
"originator_did": "did:hive:morph",
"asking_seen_usd": "0.05",
"offer_usd": "0.0325",
"offer_atomic_usdc_base": "32500",
"tx_pre_signed": "0x...",
"expires": "2026-04-27T20:30:00Z",
"attribution": {
"agent": "hive-mcp-barter",
"attribution_id": "barter-{uuid}",
"policy": "single-shot-no-haggle"
}
}
The pre-signed transaction is the entire commitment. The target accepts by broadcasting; we never have to re-sign on accept.
| Category | Our buy floor | Our resell |
|---|---|---|
| LLM tokens | $0.000020 / token | $0.000040 / token |
| Oracle reads | $0.0008 / read | $0.0015 / read |
| Storage writes | $0.00012 / write | $0.00025 / write |
| KYC checks | $0.04 / check | $0.08 / check |
If target_asking × counter_pct ≤ our_resell × 0.95, we counter. Otherwise we skip — there is no margin.
| Cap | Value |
|---|---|
| Max single counter | $0.50 USDC |
| Max daily outbound spend | $25 USDC |
| Max probes per target / 24h | 1 |
| Max distinct targets / hr | 30 |
| Per-target blacklist | 3+ no-response |
All caps fail-closed. Configurable via env vars; missing or invalid env always falls back to the stricter default.
| Env | Required | Default | Notes |
|---|---|---|---|
PORT | no | 3000 | |
ENABLE_OUTBOUND | no | false | Default-off. The 5-min cron loop only runs when set to true. |
WALLET_ADDRESS | no | 0x15184…436e | W1 MONROE on Base. |
USDC_BASE | no | 0x833589…2913 | USDC contract on Base. |
BASE_RPC | no | `https://mainnet.base.o |