Model Context Protocol (SSE / Streamable HTTP)

Power your AI coding agents with DevTools MCP

A unified, high-performance MCP server exposing exact token counting, live URL inspection, Open Graph generation, spreadsheet parsing, and markdown publishing to Claude Code, Cursor, and any MCP client.

https://devtools.devlabz.in/api/mcp

Live SSE Endpoint

Agent Prompts & Workflows

Select any scenario below to copy ready-made instructions directly into your AI assistant.

Agent Prompt Generator & Templates

Select a prompt template to copy directly into your AI assistant or project rules.

Prompt Preview

You have access to the DevTools MCP server at https://devtools.devlabz.in/api/mcp with 7 high-performance tools:

1. count_tokens: Exact token counting and pricing estimation for GPT-4o, Claude 3.5 Sonnet, Llama 3, etc. Call this before large batch LLM jobs or when verifying prompt sizes.
2. render_og_image: Generates dynamic OpenGraph and Twitter cards (terminal, minimal, modern templates) and returns a hosted URL.
3. inspect_url: Scans any live URL for social tags (Open Graph, Twitter card, canonical links) and diagnoses missing or oversized tags.
4. validate_email: Validates email syntax, performs live DNS MX lookups to confirm the domain can receive mail, and catches domain typos.
5. verify_jwt: Verifies JWT signatures, algorithms, issuer, and expiry against secrets or RSA/ECDSA public keys.
6. sheet_to_json: Reads binary XLSX, XLS, or CSV files from base64 or URL and pages through rows with column extraction.
7. publish_markdown: Publishes markdown to a live shareable URL (15-day lifetime, requires an API key).

Always prefer calling these tools for exact calculations, live web checks, and document sharing.

Connect Your Assistant

Paste the configuration snippet into your tool of choice. No API key needed for anonymous tools.

terminal

claude mcp add --transport http devtools https://devtools.devlabz.in/api/mcp

Tools Catalogue & Reference

Dynamically synchronized with the live MCP capability registry.

Count tokens

count_tokens

Count the exact BPE tokens in a piece of text for a given model, and estimate what it would cost as input. Use this instead of guessing token counts.

AnonymousWeight: 1

Example ask: “Count the tokens in this file for gpt-4o and tell me what a single prompt would cost.”

Parameters

Name	Type	Required	Description
text	string	Yes	The text to tokenize
model	string	Yes	The model whose tokenizer and pricing to use. One of: gpt-5, gpt-5-mini, gpt-5-nano, gpt-4, gpt-4o, gpt-4o-mini, gpt-4-turbo, gpt-4-32k, gpt-3.5-turbo, gpt-3.5-turbo-16k, gpt-3.5-turbo-instruct, claude-haiku-3, claude-haiku-3.5, claude-sonnet-3.5, claude-sonnet-4, claude-opus-4, text-embedding-ada-002, text-embedding-3-small, text-embedding-3-large, gemini-1, gemini-1.5

Render an Open Graph image

render_og_image

Render a 1200x630 social card and return a permanent image URL. Use this to give a page, post, or release a link preview. Returns a URL, never image bytes. Cursive scripts such as Arabic and Devanagari are not supported by the renderer.

AnonymousWeight: 5

Example ask: “Make an OG image for my release post titled 'v2.0 is out' with the ember palette.”

Parameters

Name	Type	Required	Description
title	string	Yes	The headline on the card
subtitle	optional	Optional	—
eyebrow	optional	Optional	—
badge	optional	Optional	—
footer	optional	Optional	—
template	optional	Optional	Card layout
palette	optional	Optional	—
pattern	optional	Optional	—
fontPair	optional	Optional	—
name	optional	Optional	Saved card name. Ignored without an API key.

Inspect a page's social tags

inspect_url

Fetch a URL and report its Open Graph and Twitter card tags, plus a list of missing or malformed tags. Use this to check how a link will unfurl before shipping it.

AnonymousWeight: 4

Example ask: “Check whether my blog post's social tags are complete.”

Parameters

Name	Type	Required	Description
url	string	Yes	The absolute URL of the page to inspect

Validate an email address

validate_email

Check an email address for correct syntax and confirm through a live DNS MX lookup that its domain can receive mail. Also suggests a correction for common domain typos. This does not confirm the mailbox itself exists.

AnonymousWeight: 2

Example ask: “Is support@gmial.com a real deliverable address?”

Parameters

Name	Type	Required	Description
email	string	Yes	The email address to check

Verify a JWT signature

verify_jwt

Verify a JWT's signature, expiry, and issuer against a secret or public key. Returns the header and payload only when the signature checks out. This does not decode unverified tokens — do that yourself, the payload is plain base64.

AnonymousWeight: 1

Example ask: “Verify this token against my HS256 secret and tell me when it expires.”

Parameters

Name	Type	Required	Description
token	string	Yes	The JWT to verify
secret	string	Yes	The shared secret for HMAC algorithms, or the PEM public key for RSA and ECDSA
algorithms	optional	Optional	Restrict the accepted algorithms. Strongly recommended.
issuer	optional	Optional	—

Read a spreadsheet as JSON

sheet_to_json

Read an xlsx, xls, or csv file and return its rows as JSON, one page at a time. Accepts base64 or a URL. Use this for binary spreadsheets you cannot read directly. Returns 100 rows by default — pass offset to page through a larger file.

AnonymousWeight: 5

Example ask: “Read the first 50 rows of this xlsx and tell me what the columns mean.”

Parameters

Name	Type	Required	Description
fileBase64	optional	Optional	The spreadsheet as base64. Max 8 MB decoded. Use this or url, not both.
url	optional	Optional	A URL to fetch the spreadsheet from
sheet	optional	Optional	Which sheet to read. Defaults to the first.
offset	default	Optional	—
limit	default	Optional	—

Publish markdown to a URL

publish_markdown

Publish a markdown document and get back a shareable URL that renders it with its own social card. Links live for 15 days. Requires an API key.

Keyed TierWeight: 3

Example ask: “Publish these release notes and give me the link.”

Parameters

Name	Type	Required	Description
content	string	Yes	The markdown document to publish
title	optional	Optional	Defaults to the document's first heading
access	default	Optional	READ gives a read-only link. EDIT lets anyone with the link change it.

Authentication & Key Management

Anonymous usage gives you 60 req/min for read utilities. Generate a free API key to unlock 300 req/min and write tools like publish_markdown.

Loading your API keys...

Using your API key with MCP clients

Add the Authorization header to your client configuration:

{
  "mcpServers": {
    "devtools": {
      "type": "http",
      "url": "https://devtools.devlabz.in/api/mcp",
      "headers": {
        "Authorization": "Bearer dtm_YOUR_KEY_HERE"
      }
    }
  }
}

Rate Limits & Quotas

Enforced via sliding-window token bucket. Heavy computations carry weighted costs.

Tier	Budget	Window	Payload Output Cap	Available Tools
Anonymous (IP)	60 units	60 seconds	100 KB	6 read tools
Keyed (Bearer)	300 units	60 seconds	100 KB	All 7 tools (incl. publish)

Search DevTools

Power your AI coding agents with DevTools MCP

Agent Prompts & Workflows

Agent Prompt Generator & Templates

Connect Your Assistant

Tools Catalogue & Reference

Count tokens

Parameters

Render an Open Graph image

Parameters

Inspect a page's social tags

Parameters

Validate an email address

Parameters

Verify a JWT signature

Parameters

Read a spreadsheet as JSON

Parameters

Publish markdown to a URL

Parameters

Authentication & Key Management

Using your API key with MCP clients

Rate Limits & Quotas