# Assay: settlement verification (remote · fomox.io)

Verify crypto payments really settled and how much arrived. 20 chains. Read only, no API key.

- Trust score: 63/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-09-29

## Components

- remote · `fomox.io`: 63/100 (this document), [markdown](https://verifymcp.io/servers/io-fomox-assay/api-assay-mcp.md), [page](https://verifymcp.io/servers/io-fomox-assay/api-assay-mcp)

## Channel facts

- Endpoint: `https://fomox.io/api/assay/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `1.0.0`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-09-29.

- **Endpoint Security**: 57/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation not fully verified: no authorisation is required to call this server, and 6 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe.
  - HTTPS is enforced; there's no plaintext access path.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 69/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 1169 tokens (~194/item across 6 items; 6 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 10/100
  - Stability observed for 3 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 6 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 7 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 60/100
  - Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28.

## Install

### How do I install the Assay: settlement verification MCP server?

Assay: settlement verification is a hosted endpoint at https://fomox.io/api/assay/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add --transport http io-fomox-assay 'https://fomox.io/api/assay/mcp'
```

### Cursor

```json
{
  "mcpServers": {
    "io-fomox-assay": {
      "url": "https://fomox.io/api/assay/mcp"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "io-fomox-assay": {
      "type": "http",
      "url": "https://fomox.io/api/assay/mcp"
    }
  }
}
```

### Codex

```toml
[mcp_servers.io-fomox-assay]
url = "https://fomox.io/api/assay/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "io-fomox-assay": {
      "type": "remote",
      "url": "https://fomox.io/api/assay/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add io-fomox-assay --url 'https://fomox.io/api/assay/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  io-fomox-assay:
    url: "https://fomox.io/api/assay/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "io-fomox-assay": {
      "Transport": "http",
      "Url": "https://fomox.io/api/assay/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add io-fomox-assay -t streamable-http -u 'https://fomox.io/api/assay/mcp'
```

### Other

```json
{
  "mcpServers": {
    "io-fomox-assay": {
      "type": "http",
      "url": "https://fomox.io/api/assay/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-09-28 (score 63, +1)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-09-27 (score 62, 0)

- [functional improvement] Stability: unverified → 0.03

### 2026-09-26 (score 62)

First indexed and scored.

## MCP tools (6)

### `verify_payment` (~445 tokens)

Check whether a crypto payment really settled and how much was ACTUALLY delivered, which is often not the amount the transaction claims. Use this before crediting anyone for an incoming payment.

Returns `delivered` (what truly moved), `claimed` (what the transaction says), `mismatch` (true when they disagree), and `warnings` naming the specific trap with a remedy. `ok` is true ONLY when the payment is final and meets everything you asserted in `expect`; anything uncertain returns ok:false, so it is safe to gate a credit on `ok`.

Chains: xrp, hedera, algorand, solana, ethereum, base, arbitrum, optimism, polygon, bnb, avalanche, linea, scroll, zksync, blast, mantle, celo, gnosis, bitcoin, litecoin.
Pass `expect` whenever you can. Without it this reports what happened; with it, it tells you whether to pay.
Read only: this never moves funds and never holds keys.

Input parameters:

- `chain` (string): Chain id. One of: xrp, hedera, algorand, solana, ethereum, base, arbitrum, optimism, polygon, bnb, avalanche, linea, scroll, zksync, blast, mantle, celo, gnosis, bitcoin, litecoin. Common aliases wor…
- `expect` (object): What you believe should be true. Supplying this is what lets `ok` mean anything.
- `ref` (string, required): The transaction hash or id. EVM: 0x + 64 hex. XRP: 64 hex. Solana: base58 signature. Bitcoin: 64 hex. Hedera: 0.0.1234-1700000000-123456789. Algorand: 52 base32 chars. Or a sandbox case like sandbox:…
- `rpcUrl` (string): Optional. Your own HTTPS RPC endpoint for this chain. Bypasses our rate limits entirely and usually returns faster.

### `list_chains` (~58 tokens)

List every chain this service can verify, with the confirmation depth each needs before a payment is treated as final, and how deeply it can be verified. Call this if you are unsure whether a chain is supported or what to pass as `chain`.

### `list_failure_modes` (~138 tokens)

List every known way a blockchain payment can appear successful while being worth less than it claims, or nothing at all. Each entry explains what the chain does, what it costs you when you get it wrong, and the one-line fix.

Useful when writing or reviewing code that credits users for incoming crypto payments. Every chain has its own dialect but they are all the same few lies, and the mitigation is always the same: never trust the stated amount, reconstruct what actually moved.

Input parameters:

- `family` (string): Optionally filter to one family: xrpl, evm, utxo, svm, hedera, algorand, or all.

### `evaluate_spend_policy` (~229 tokens)

Check a proposed payment against spending limits that live OUTSIDE your context, where no instruction in a prompt, a message or a web page can change them. Returns a signed allow or deny with reasons.

Use this before executing any transfer on behalf of a user. It enforces velocity caps, per-action ceilings, recipient allowlists and asset allowlists. Because the rules are held server side and signed, an attacker who takes over your reasoning still cannot raise your limits.

IMPORTANT: this is ADVISORY. Assay holds no keys and cannot stop a transaction. Verify the signature and enforce the decision wherever you sign. Create a policy first with the /v1/policy endpoint.

Input parameters:

- `action` (object, required): The payment you are about to make.
- `commit` (boolean): Default true: an allowed action counts against velocity limits. Pass false to ask 'would this be allowed' without consuming budget.
- `policyId` (string, required): From creating a policy.
- `policySecret` (string, required): The secret returned when the policy was created. Shown once, stored only as a hash.

### `run_sandbox_case` (~114 tokens)

Practise on a payment designed to deceive you, with no money at risk. Returns a verification result shaped exactly like a real one for one of 19 adversarial cases. Decide whether you would credit it, then call check_sandbox_answer to find out whether you were right and what the mistake would have cost.

Use this to test any agent or integration that handles incoming crypto payments BEFORE it handles real money.

Input parameters:

- `caseId` (string): Which case to run. Omit to get the list of available cases.

### `check_sandbox_answer` (~118 tokens)

Score your decision on a sandbox case. Tell it whether you would have credited the payment and for how much, and it replies with whether that was correct and, if not, exactly what the error would have cost you in real units. This is the fastest way to find out whether your payment handling is actually safe.

Input parameters:

- `amount` (string): If crediting, how much, in the asset's smallest units.
- `caseId` (string, required): The case you ran.
- `credit` (boolean, required): Would you have credited this payment?

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/io-fomox-assay/api-assay-mcp#diagnostics

## Score history

- 2026-09-29: 63
- 2026-09-28: 63
- 2026-09-27: 62
- 2026-09-26: 62

## Common questions

### What is the Assay: settlement verification MCP server?

Assay: settlement verification is an MCP server listed in the public MCP registry as io.fomox/assay. Verify crypto payments really settled and how much arrived. 20 chains. Read only, no API key. This page covers its hosted endpoint (https://fomox.io/api/assay/mcp).

### Is the Assay: settlement verification MCP server safe to use?

Assay: settlement verification scores 63 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the Assay: settlement verification MCP server expose?

Assay: settlement verification exposes 6 tools: verify_payment, list_chains, list_failure_modes, evaluate_spend_policy, run_sandbox_case, check_sandbox_answer. Their descriptions and schemas cost roughly 1,102 tokens of context every time the server is loaded.

### Does the Assay: settlement verification MCP server require authentication?

No. We connected to Assay: settlement verification without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

### Is the Assay: settlement verification MCP server still maintained?

Assay: settlement verification is still listed as active in the MCP registry. We last reached this channel on 29 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

## Links

- Remote endpoint: https://fomox.io/api/assay/mcp
- Website: https://fomox.io/assay
- Changelog RSS feed: https://verifymcp.io/servers/io-fomox-assay/api-assay-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/io-fomox-assay/api-assay-mcp.json
- HTML version of this page: https://verifymcp.io/servers/io-fomox-assay/api-assay-mcp