This MCP server decodes EVM bytes into JSON. It provides an event-log decoder, a calldata explainer, selector lookup, and ABI fetching. The primary function is transforming low-level on-chain byte data (such as logs and calldata) into structured JSON outputs suitable for inspection and analysis.

🛠️ Key Features

Decode EVM bytes to JSON
Event-log decoder
Calldata explainer
Selector lookup
ABI fetch

🚀 Use Cases

Interpret EVM event logs and convert them to JSON
Explain and inspect calldata by producing readable JSON
Look up selectors associated with on-chain interfaces
Fetch ABI information to support decoding and interpretation

⚡ Developer Benefits

Structured JSON decoding for EVM byte data
Built-in tools for logs, calldata, selector resolution, and ABI retrieval

⚠️ Limitations

Description does not specify supported EVM networks, input formats, error handling, or performance characteristics

FabTally Decode — MCP server

Developer on-chain decoding reads that turn raw EVM bytes into human-readable JSON — the capability buried inside $49-999/mo RPC plans. Fronts the Decode HTTP API at https://decode.fabtally.com. Holds no private key.

Tools (all paid; a call with no payment returns the decoded x402 402 challenge)

Tool	Price	What it does
`decode_log`	$0.003	Flagship. Decode event LOGS to JSON. `{chain, tx_hash}` decodes every log in a tx, or `{chain, address, topics[], data}` a single log; optional `abi`. Returns event name + canonical signature + named/typed args — handling tuple/array/nested params, anonymous events, indexed vs non-indexed. Resolves ABI via Sourcify/Blockscout + 4byte when none is given.
`decode_calldata`	$0.002	Decode a function call. `{chain, to?, data, abi?}` → selector resolved to a function signature (provided ABI / verified source / 4byte.directory) + fully decoded typed arguments.
`selector_lookup`	$0.001	Resolve a 4-byte function selector (`0x`+8 hex) or a 32-byte event topic (`0x`+64 hex) to human signature(s) via 4byte.directory + openchain.xyz, with a verified flag.
`abi_fetch`	$0.002	Fetch a contract's verified ABI + metadata (Sourcify/Blockscout) + verification status + full proxy-implementation resolution (EIP-1967/1822/OZ-legacy/beacon) — returns the implementation ABI for proxies. Args: `address`, `chain`.

Chains: ethereum, base, arbitrum, optimism, polygon, bsc.

Every tool also accepts an optional x_payment (base64 x402 payload) that is forwarded as the X-PAYMENT header to settle the call and return the real result. Humans can instead prepay by card and use an X-FabTally-Key credit key against the HTTP API.

Transports

stdio (portable): npx fabtally-decode-mcp (bin: fabtally-decode-mcp)
streamable-http (hosted): https://decode.fabtally.com/mcp

Config: FABTALLY_DECODE_BASE (default https://decode.fabtally.com).

Read-only, keyless, stateless, descriptive. Operated by Sunstone Soft (fabtally.com). Not a security guarantee or financial advice.

chain	string	required	EVM chain: ethereum \| base \| arbitrum \| optimism \| polygon \| bsc.
to	string	optional	Contract address the call targets (optional; enables verified-ABI resolution).
data	string	required	Calldata (0x hex, at least the 4-byte selector).
abi	any	optional	Optional contract ABI (JSON array or JSON string). If omitted, the ABI is resolved from the verified source (Sourcify/Blockscout) or 4byte.directory.
x_payment	string	optional	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 challenge first.

selector	string	required	A 4-byte function selector (0x + 8 hex) or a 32-byte event topic hash (0x + 64 hex).
x_payment	string	optional	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 challenge first.

chain	string	required	EVM chain: ethereum \| base \| arbitrum \| optimism \| polygon \| bsc.
address	string	required	Contract address (0x + 40 hex).
x_payment	string	optional	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 challenge first.

FabTally Decode

🛠️ Key Features

🚀 Use Cases

⚡ Developer Benefits

⚠️ Limitations

decode_log

decode_calldata

selector_lookup

abi_fetch

FabTally Decode — MCP server

Tools (all paid; a call with no payment returns the decoded x402 402 challenge)

Transports

Install

Remote endpoint