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com.formatho/runtime

by formatho.com · remote · local (oci) · no sign-in to list tools · v0.3.0 · published by com.formatho

Self-hosted MCP server: 26 deterministic dev, security, and EVM tools.

Final · 2Changes · 20
CompareRegistry entry

26 tools: 2 do something that can't be undone, 20 change things and 4 only read.

Scanned Oct 21, 2026

No check matched anything in the tool definitions. No finding is not a safety guarantee. How the checks work.

claude mcp add --transport http runtime https://mcp.formatho.com/mcp

Tools

Open a tool for its reasons and full description. Descriptions are the publisher's own words, shown as they are.

26 tools

Can't be undone 2Claude Code: ask
  • case.convertConvert an identifier between camelCase, snake_case, kebab-case, CONSTANT_CASE, and Title Case.No findings

    Why it is in this group

    • The name "case.convert" says "convert": a word for a change.
    • The input addresses people (input.to): what it sends cannot be taken back.
    Description, as the server wrote it
    Convert an identifier between camelCase, snake_case, kebab-case, CONSTANT_CASE, and Title Case. [dev · v1.0.0 · deterministic: true · permissions: none]
  • evm.unit_convertConvert EVM amounts between wei, gwei, and ether with exact BigInt math.No findings

    Why it is in this group

    • The name "evm.unit_convert" says "convert": a word for a change.
    • The input addresses people (input.to): what it sends cannot be taken back.
    Description, as the server wrote it
    Convert EVM amounts between wei, gwei, and ether with exact BigInt math. [web3 · v1.0.0 · deterministic: true · permissions: none]
Changes things 20Claude Code: ask
  • base64.decodeBase64-decode to text.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Base64-decode to text. [data · v1.0.0 · deterministic: true · permissions: none]
  • base64.encodeBase64-encode text (standard alphabet).No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Base64-encode text (standard alphabet). [data · v1.0.0 · deterministic: true · permissions: none]
  • erc4626.mathExact EIP-4626 vault math in BigInt: convert assets to shares (round down) and shares to assets (round down), with optional virtual offsets.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Exact EIP-4626 vault math in BigInt: convert assets to shares (round down) and shares to assets (round down), with optional virtual offsets. [defi · v1.0.0 · deterministic: true · permissions: none]
  • evm.checksum_addressEIP-55 checksum an Ethereum address, or verify a checksummed one.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    EIP-55 checksum an Ethereum address, or verify a checksummed one. [web3 · v1.0.0 · deterministic: true · permissions: none]
  • evm.create2_addressCompute the deterministic CREATE2 address: keccak256(0xff ‖ factory ‖ salt ‖ initCodeHash)[12:].No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Compute the deterministic CREATE2 address: keccak256(0xff ‖ factory ‖ salt ‖ initCodeHash)[12:]. [web3 · v1.0.0 · deterministic: true · permissions: none]
  • evm.decode_calldataExtract the 4-byte selector from raw calldata, match it against common signatures, and decode static (word-based) arguments: address, uint256, int256, bytes32, bool.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Extract the 4-byte selector from raw calldata, match it against common signatures, and decode static (word-based) arguments: address, uint256, int256, bytes32, bool. [web3 · v1.0.0 · deterministic: true · permissions: none]
  • evm.function_selectorCompute the 4-byte function selector from a canonical signature, with reverse lookup against common signatures.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Compute the 4-byte function selector from a canonical signature, with reverse lookup against common signatures. [web3 · v1.0.0 · deterministic: true · permissions: none]
  • evm.keccak256Keccak-256 (Ethereum flavor, NOT NIST SHA3-256) of arbitrary hex or text.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Keccak-256 (Ethereum flavor, NOT NIST SHA3-256) of arbitrary hex or text. [web3 · v1.0.0 · deterministic: true · permissions: none]
  • evm.storage_slotCompute Solidity storage slots: simple variables, mapping values (keccak(key ‖ p)), and dynamic array elements (keccak(p) + index).No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Compute Solidity storage slots: simple variables, mapping values (keccak(key ‖ p)), and dynamic array elements (keccak(p) + index). [web3 · v1.0.0 · deterministic: true · permissions: none]
  • evm.v4_hook_permissionsUniswap v4 hook permissions: compute the 14-bit permission field from hook-call names, or decode the field from a hook address (bits live in the LOW 14 bits: address & 0x3FFF).No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Uniswap v4 hook permissions: compute the 14-bit permission field from hook-call names, or decode the field from a hook address (bits live in the LOW 14 bits: address & 0x3FFF). [web3 · v1.0.0 · deterministic: true · permissions: none]
  • hash.textHash text with md5/sha1/sha256/sha384/sha512 (hex output).No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Hash text with md5/sha1/sha256/sha384/sha512 (hex output). MD5/SHA1 are for compatibility checks only, not security. [security · v1.0.0 · deterministic: true · permissions: none]
  • hex.encodeEncode text to hex, or decode hex (with or without 0x) to text.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Encode text to hex, or decode hex (with or without 0x) to text. [data · v1.0.0 · deterministic: true · permissions: none]
  • jwt.decodeDecode a JWT (JWS compact serialization) header and claims WITHOUT verifying the signature.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Decode a JWT (JWS compact serialization) header and claims WITHOUT verifying the signature. Reports expiry status from the exp claim. [security · v1.0.0 · deterministic: true · permissions: none]
  • random.stringGenerate a cryptographically random alphanumeric string.No findings

    Why it is in this group

    • The description's first verb is "generate": a word for a change.
    Description, as the server wrote it
    Generate a cryptographically random alphanumeric string. [security · v1.0.0 · deterministic: false · permissions: none]
  • regex.testTest a regular expression against text: match result plus all capture groups.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Test a regular expression against text: match result plus all capture groups. [dev · v1.0.0 · deterministic: true · permissions: none]
  • slug.generateConvert text to a URL-safe kebab-case slug.No findings

    Why it is in this group

    • The name "slug.generate" says "generate": a word for a change.
    Description, as the server wrote it
    Convert text to a URL-safe kebab-case slug. [dev · v1.0.0 · deterministic: true · permissions: none]
  • timestamp.convertConvert Unix seconds/milliseconds to ISO 8601 (UTC) and back.No findings

    Why it is in this group

    • The name "timestamp.convert" says "convert": a word for a change.
    Description, as the server wrote it
    Convert Unix seconds/milliseconds to ISO 8601 (UTC) and back. [dev · v1.0.0 · deterministic: true · permissions: none]
  • url.decodeDecode percent-encoded text.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Decode percent-encoded text. [network · v1.0.0 · deterministic: true · permissions: none]
  • url.encodePercent-encode text (component encoding).No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Percent-encode text (component encoding). [network · v1.0.0 · deterministic: true · permissions: none]
  • uuid.v4Generate random UUID v4 values.No findings

    Why it is in this group

    • The description's first verb is "generate": a word for a change.
    Description, as the server wrote it
    Generate random UUID v4 values. [security · v1.0.0 · deterministic: false · permissions: none]
Only reads 4Claude Code: allow
  • formatho.registryList every registered Formatho tool with version, category, deterministic flag, permissions, and Formatho Verified status.No findings

    Why it is in this group

    • The description's first verb is "list": a word for reading.
    Description, as the server wrote it
    List every registered Formatho tool with version, category, deterministic flag, permissions, and Formatho Verified status. [meta · v1.0.0 · deterministic: true · permissions: none]
  • json.formatValidate and pretty-print JSON with a configurable indent level.No findings

    Why it is in this group

    • The description's first verb is "validate": a word for reading.
    Description, as the server wrote it
    Validate and pretty-print JSON with a configurable indent level. [data · v1.0.0 · deterministic: true · permissions: none]
  • json.minifyValidate JSON and strip all insignificant whitespace.No findings

    Why it is in this group

    • The description's first verb is "validate": a word for reading.
    Description, as the server wrote it
    Validate JSON and strip all insignificant whitespace. [data · v1.0.0 · deterministic: true · permissions: none]
  • json.validateValidate JSON and report the parse error position if invalid.No findings

    Why it is in this group

    • The name "json.validate" says "validate": a word for reading.
    Description, as the server wrote it
    Validate JSON and report the parse error position if invalid. [data · v1.0.0 · deterministic: true · permissions: none]

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Install

Pinned to version 0.3.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http runtime https://mcp.formatho.com/mcp

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json
{
  "permissions": {
    "allow": [
      "mcp__runtime__json_format",
      "mcp__runtime__json_minify",
      "mcp__runtime__json_validate",
      "mcp__runtime__formatho_registry"
    ],
    "ask": [
      "mcp__runtime__base64_encode",
      "mcp__runtime__base64_decode",
      "mcp__runtime__url_encode",
      "mcp__runtime__url_decode",
      "mcp__runtime__slug_generate",
      "mcp__runtime__hash_text",
      "mcp__runtime__uuid_v4",
      "mcp__runtime__random_string",
      "mcp__runtime__jwt_decode",
      "mcp__runtime__evm_keccak256",
      "mcp__runtime__evm_function_selector",
      "mcp__runtime__evm_create2_address",
      "mcp__runtime__evm_storage_slot",
      "mcp__runtime__evm_decode_calldata",
      "mcp__runtime__evm_v4_hook_permissions",
      "mcp__runtime__erc4626_math",
      "mcp__runtime__timestamp_convert",
      "mcp__runtime__regex_test",
      "mcp__runtime__case_convert",
      "mcp__runtime__hex_encode",
      "mcp__runtime__evm_checksum_address",
      "mcp__runtime__evm_unit_convert"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. It assumes the server is installed as runtime. Review it before you use it.