Deterministic tools for AI agents.

Deterministic tools for AI agents.

More reliable than AI inference. A lightweight utility API suite for developers and AI agents.

{
  "mcpServers": {
    "thousand-api": {
      "url": "https://mcp.thousand-api.com/mcp",
      "headers": { "x-api-key": "your-api-key" }
    }
  }
}

Save LLM tokens and ensure accurate results

When AI agents use tools, they get accurate results with fewer tokens than having the LLM process everything itself.

Two approaches to reducing tokens

① Use tools to reduce output tokens

e.g. 95% reduction with HTML→text extraction

② Turn off unused tools to reduce tool-definition tokens

  • Configure per category or per tool from the dashboard
  • All 55 tools → 20 tools cuts tool-definition tokens by about 64%

Common filtering presets:

  • Developer set (6 tools) → Security + Data processing
  • Document set (5 tools) → Text + Format conversion
  • Research set (5 tools) → Network

94%

Token reduction

HTML to text

64%

Token reduction

Postal code lookup

67%

Token reduction

Compound interest

60%

Token reduction

HMAC verification

Without tools

Input
8,200 TOKEN
Output
1,100 TOKEN

Total: 9,300 TOKEN

With tools

Input
380 TOKEN
Output
160 TOKEN

Total: 540 TOKEN

94% saved

What AI agents struggle with—done reliably

Close LLM weak spots we’ve verified in practice—with tools that don’t guess.

Live data

LLMs only know what they were trained on

  • DNS lookup: Misstated GitHub’s MX as “Gmail” (correct: Microsoft 365)
  • FX rates: Guessed a range like “~161–162 yen” (Thousand API returns exact values)
  • URL redirects: Invented a fictional destination for shortened URLs

Reliable generation

LLMs invent plausible-looking values

  • SHA-256 / HMAC: Produced fake hashes that only look correct
  • ISBN validation: Marked every valid ISBN-13 as invalid
  • UUID generation: No cryptographic randomness guarantee

Boundary-sensitive math

LLMs only approximate the hard edges

  • Business days: Off-by-one from how the start date is counted
  • JWT expiry: Unix time conversion off by 6+ hours
  • Map tile coordinates: ~10 tiles off on the Y axis

AI makes mistakes. We tested it.

We asked the same questions to a general AI chat and Thousand API (MCP-connected).

🔐 SHA-256 hash generation

General AI chat

aa69305e7a9… (a value that was not actually correct)

Thousand API

Returns the correct SHA-256 hash instantly

🌐 DNS lookup (github.com MX)

General AI chat

aspmx.l.google.com (stale training data)

Thousand API

outlook.com (the live MX record)

🔗 Short URL resolution

General AI chat

Confidently answered with a URL that does not exist

Thousand API

Follows HTTP redirects and returns the final URL

📅 Business days (10 days after June 27)

General AI chat

July 28 (off by one from inclusive start-date counting)

Thousand API

July 29 (exact, per the specification)

July 2026 / Compared with ChatGPT Free

Use cases

Hand agents MCP tools for work that breaks when left to inference

AI assistant

Scheduling for AI assistants

Meeting times and reminders drift when agents infer business days, time zones, or cron schedules.

Related tools

  • Holiday & Business Day
  • Cron Parser
Learn more

AI marketing

Prep work for AI writers and marketers

Outlines and competitor research suffer when meta tags and post timing are guessed.

Related tools

  • Page Meta / OGP
  • QR Code Generator
  • Holiday & Business Day
Learn more

Cursor / Claude dev

Precise utilities for AI engineers

JSON, cron, and URLs in generated code introduce subtle spec mistakes.

Related tools

  • JSON Validator
  • Cron Parser
  • URL Redirect Resolver
Learn more

Chatbot

External sensors for chatbots

Bots lack live locale, link targets, and final URLs for short links.

Related tools

  • IP Geolocation
  • Page Meta / OGP
  • QR Code Generator
  • URL Redirect Resolver
Learn more

MCP Tools

Reliable utility MCP tools for AI agents and developers

84 MCP tools available

On “10 business days later,” typical LLMs often miscount the start date. Thousand API calculates exactly to the specification.

Code generation, text processing, and Japanese conversion with reliable, token-efficient APIs

Format conversions for AI-generated data with zero tokens

Extract values from large JSON, validate schemas, compute statistics

Typical LLMs pretend to know DNS records and URL contents. Thousand API actually fetches and verifies them.

SHA-256 and HMAC invite LLMs to invent plausible fake values. Thousand API performs real cryptographic computation.

Distance, coordinates, color tools, and version comparison with deterministic results

Tool names, endpoints, parameters, and response examples are in the

MCP tool index →

Works as an MCP server

Connect directly to Claude or Cursor. Copy the config and your AI agent can call Thousand API tools right away.

Supported clients

  • Claude
  • Cursor
  • Other MCP-compatible tools
{
  "mcpServers": {
    "thousand-api": {
      "url": "https://mcp.thousand-api.com/mcp",
      "headers": { "x-api-key": "your-api-key" }
    }
  }
}

Pricing

50+ MCP tools free for up to 1,000 requests/month. Upgrade as you scale.

Free

Free

Trial and light personal use

  • MCP server connection
  • REST API access
  • API keys1
  • Monthly requests1,000
  • Email support
  • Priority support
Get Started
Recommended

Starter

¥480/mo

Everyday personal use

  • MCP server connection
  • REST API access
  • API keys5
  • Monthly requests10,000
  • Email support
  • Priority support
Start Starter

Pro

¥1,980/mo

Power users and small teams

  • MCP server connection
  • REST API access
  • API keys20
  • Monthly requests100,000
  • Email support
  • Priority support
Start Pro