# FabTally Decode (remote · decode.fabtally.com)

Decode EVM bytes to JSON: event-log decoder, calldata explainer, selector lookup, ABI fetch.

- Trust score: 59/100 (low)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-08-03

## Components

- remote · `decode.fabtally.com`: 59/100 (this document), [markdown](https://verifymcp.io/servers/zvmzaretsky-onchain-decode/decode.md), [page](https://verifymcp.io/servers/zvmzaretsky-onchain-decode/decode)

## Channel facts

- Endpoint: `https://decode.fabtally.com/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 2026-08-03.

- **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 4 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**: 51/100
  - AI-judged instruction clarity (good).
  - Context-footprint check failed: tool/resource definitions use about 1009 tokens (~252/item across 4 items; 4 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 7/100
  - Stability observed for 2 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.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### Claude

```bash
claude mcp add --transport http zvmzaretsky-onchain-decode https://decode.fabtally.com/mcp
```

### Codex

```toml
[mcp_servers.zvmzaretsky-onchain-decode]
url = "https://decode.fabtally.com/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "zvmzaretsky-onchain-decode": {
      "type": "remote",
      "url": "https://decode.fabtally.com/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add zvmzaretsky-onchain-decode --url https://decode.fabtally.com/mcp --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  zvmzaretsky-onchain-decode:
    url: "https://decode.fabtally.com/mcp"
```

### Other

```json
{
  "mcpServers": {
    "zvmzaretsky-onchain-decode": {
      "type": "http",
      "url": "https://decode.fabtally.com/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.

### 2026-08-03 (score 59, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-08-02 (score 58, 0)

- [functional improvement] Stability: unverified → 0.03

### 2026-08-01 (score 58)

First indexed and scored.

## MCP tools (4)

### `decode_log` (~354 tokens)

Decode event logs to typed JSON (paid $0.003)

PAID $0.003 (x402, USDC on Base). FLAGSHIP: decode EVM event LOGS to human-readable JSON. Give {chain, tx_hash} to decode every log in a transaction, OR {chain, address, topics[], data} for a single log; optional {abi}. Returns each event's name, canonical signature and named/typed args — correctly handling tuple/array/nested params, anonymous events, and indexed vs non-indexed. Resolves the ABI via Sourcify/Blockscout + 4byte event signatures when none is supplied. Without payment returns the x402 challenge; pass x_payment to settle.

Input parameters:

- `abi`: Optional contract ABI (JSON array or JSON string). If omitted, the ABI is resolved from the verified source (Sourcify/Blockscout) or 4byte.directory.
- `address` (string): Contract address of a single log (used with topics + data).
- `chain` (string, required): EVM chain: ethereum | base | arbitrum | optimism | polygon | bsc.
- `data` (string): Log data field (0x hex) holding the non-indexed args.
- `topics` (array): Log topics array (topic0 is the event signature hash for non-anonymous events).
- `tx_hash` (string): Transaction hash (0x + 64 hex) — decodes every event log in the tx.
- `x_payment` (string): x402 payment payload (base64) for this PAID decode. If supplied it is forwarded as the X-PAYMENT header to settle the call and return the real result instead of a 402 challenge. Omit to get the price…

### `decode_calldata` (~255 tokens)

Decode a function call's calldata (paid $0.002)

PAID $0.002 (x402, USDC on Base). Decode a contract function call. Give {chain, to?, data, abi?}; get the 4-byte selector resolved to a function signature (via provided ABI, the verified contract source, or 4byte.directory) plus fully decoded, typed arguments (tuples/arrays/nested included). Without payment returns the x402 challenge.

Input parameters:

- `abi`: Optional contract ABI (JSON array or JSON string). If omitted, the ABI is resolved from the verified source (Sourcify/Blockscout) or 4byte.directory.
- `chain` (string, required): EVM chain: ethereum | base | arbitrum | optimism | polygon | bsc.
- `data` (string, required): Calldata (0x hex, at least the 4-byte selector).
- `to` (string): Contract address the call targets (optional; enables verified-ABI resolution).
- `x_payment` (string): x402 payment payload (base64) for this PAID decode. If supplied it is forwarded as the X-PAYMENT header to settle the call and return the real result instead of a 402 challenge. Omit to get the price…

### `selector_lookup` (~192 tokens)

Resolve a selector or event topic to a signature (paid $0.001)

PAID $0.001 (x402, USDC on Base). Resolve a 4-byte function selector (0x + 8 hex) OR a 32-byte event topic hash (0x + 64 hex) to its human-readable signature(s) via 4byte.directory + openchain.xyz. Returns all matches (selectors can collide) with a verified flag. Without payment returns the x402 challenge; pass x_payment to settle.

Input parameters:

- `selector` (string, required): A 4-byte function selector (0x + 8 hex) or a 32-byte event topic hash (0x + 64 hex).
- `x_payment` (string): x402 payment payload (base64) for this PAID decode. If supplied it is forwarded as the X-PAYMENT header to settle the call and return the real result instead of a 402 challenge. Omit to get the price…

### `abi_fetch` (~208 tokens)

Fetch a contract's verified ABI + proxy resolution (paid $0.002)

PAID $0.002 (x402, USDC on Base). Fetch the verified ABI + metadata for a contract. Give {address, chain}; get the ABI JSON, verification status/source (Sourcify or Blockscout), the callable function/event signatures, and full proxy-implementation resolution (EIP-1967/1822/OZ-legacy/beacon) — returning the implementation's ABI when it's a proxy. Without payment returns the x402 challenge; pass x_payment to settle.

Input parameters:

- `address` (string, required): Contract address (0x + 40 hex).
- `chain` (string, required): EVM chain: ethereum | base | arbitrum | optimism | polygon | bsc.
- `x_payment` (string): x402 payment payload (base64) for this PAID decode. If supplied it is forwarded as the X-PAYMENT header to settle the call and return the real result instead of a 402 challenge. Omit to get the price…

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/zvmzaretsky-onchain-decode/decode#diagnostics

## Score history

- 2026-08-03: 59
- 2026-08-02: 58
- 2026-08-01: 58

## Links

- Remote endpoint: https://decode.fabtally.com/mcp
- Repository: https://github.com/zvmzaretsky/onchain-decode-mcp
- Website: https://decode.fabtally.com/
- Changelog RSS feed: https://verifymcp.io/servers/zvmzaretsky-onchain-decode/decode/changelog.xml
- Changelog JSON feed: https://verifymcp.io/servers/zvmzaretsky-onchain-decode/decode/changelog.json
- HTML version of this page: https://verifymcp.io/servers/zvmzaretsky-onchain-decode/decode