# HTTP Content-Type & Charset Checker | URL Audit (`quanmatrix/content-type-charset-auditor`) Actor

Check public URLs for MIME types, charset declarations and related HTTP response headers, highlighting observed metadata and security problems.

- **URL**: https://apify.com/quanmatrix/content-type-charset-auditor.md
- **Developed by:** [Rafael Barreto Haddad](https://apify.com/quanmatrix) (community)
- **Categories:** Developer tools, SEO tools, Automation
- **Security:** Limited permissions
- **Stats:** 2 total users, 1 monthly users, 100.0% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $0.78 / 1,000 results

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.
Since this Actor supports Apify Store discounts, the price gets lower the higher subscription plan you have.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

An Actor is a serverless cloud program that runs on the Apify platform. It has two run modes.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.

Apify vocabulary and the platform model are defined once, in the agent quickstart at https://apify.com/agents.md.

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.

Do not guess an integration path. Every one of them is in the agent quickstart at https://apify.com/agents.md: the Apify MCP server, Agent Skills with the Apify CLI, the JavaScript and Python clients, the REST API, and the account-free path for an agent with no human to sign in. It also carries the rule on stating cost before the first paid run.

For examples already wired to this Actor's own input schema, see the [API](#api) section below.

Each client library has reference documentation the quickstart does not restate: [JavaScript/TypeScript](https://docs.apify.com/api/client/js/docs.md) (`npm install apify-client`) and [Python](https://docs.apify.com/api/client/python/docs.md) (`pip install apify-client`).

# README

## Content-Type & Charset Auditor

Audit public URLs for Content-Type correctness, charset declarations, MIME sniffing protection, HTTPS delivery, and common response metadata problems.

### Why use this Actor

API and web teams need recurring MIME and response-contract validation because wrong Content-Type or charset declarations silently break clients, browsers and crawlers.

### Key features

- Buyer-native inputs aligned to **content type contract**.
- Predictable structured output in the default Apify Dataset.
- Pay Per Event pricing tied to measurable result rows or reports.
- Optional MCP connector delivery for downstream automation and AI agents.

### Quick start

Start with this working example and replace the target values with your own:

```json
{
  "urls": [
    "https://example.com",
    "https://www.python.org"
  ]
}
```

The Actor writes structured results to the default Apify Dataset and can be used from the Store, API, schedules, Tasks, automations and MCP-compatible AI workflows.

### Input

- `urls` — URLs: Configure URLs for this Actor run.
- `expectedKind` — Expected content kind: Configure Expected content kind for this Actor run.
- `previousSnapshots` — Previous response snapshots: Configure Previous response snapshots for this Actor run.
- `failRunOnMismatch` — Fail on MIME/contract mismatch: Configure Fail on MIME/contract mismatch for this Actor run.
- `maxUrls` — Maximum URLs: Configure Maximum URLs for this Actor run.
- `concurrency` — Concurrency: Maximum URLs audited in parallel.

All integration and advanced analysis fields are optional. The default example is intentionally runnable without configuring MCP or a previous-run baseline.

### Output

The Dataset exposes predictable machine-readable output. Representative fields include `dataset`.

### Pricing

This Actor uses Pay Per Event. The current factory base price is **$0.001000 per result event**. The Apify Store remains the source of truth for the price and plan/tier details shown to the buyer.

### Use cases

- Run the buyer-ready workflows exposed as Apify Tasks without preparing a custom integration first.
- Use the Actor from API or schedules for recurring collection, comparison or monitoring.
- Feed the structured Dataset output into spreadsheets, databases, automations or AI agents.
- Compare repeat runs when the product supports snapshots or previous-run inputs.

### Automation and AI

Use the same Actor through Apify API, schedules, public Tasks and the Apify MCP server. Outputs are structured for downstream workflows and AI agents rather than requiring manual copy/paste.

### Limitations

- Public websites and upstream APIs can change markup, access rules, rate limits or field availability without notice.
- Fields that are not publicly available are returned as unavailable or omitted rather than fabricated.
- Analytical outputs depend on the quality and coverage of the supplied or collected source data.
- Treat marketplace, reputation, workforce, safety or commercial signals as decision support and validate material decisions against the underlying source evidence.

### Detailed documentation

### Detailed documentation

Validate response MIME metadata against lightweight observed content signatures and track response-contract drift.

### Why use this Actor

Incorrect Content-Type or charset declarations can break API clients, browser rendering, downloads, crawlers, integrations, and security assumptions. Header presence alone is not always enough: a server can claim JSON while returning HTML, a proxy can remove `nosniff`, or a deployment can silently change response metadata. This Actor combines declared MIME evidence with bounded content-signature checks, expected-kind validation, and reusable snapshots so release and monitoring workflows can detect those failures deterministically.

### Key features

- Parses Content-Type media type and charset.
- Checks X-Content-Type-Options `nosniff` and HTTPS delivery.
- Performs bounded signature detection for HTML, JSON, XML, common images, PDF, text, and binary responses.
- Flags declared MIME type mismatches against observed content.
- Supports an expected content kind for release or API contract validation.
- Captures Content-Disposition as part of the response metadata snapshot.
- Emits a normalized response-contract snapshot and fingerprint.
- Compares previous snapshots and reports drift/regression evidence.
- Supports fail-after-evidence behavior for automated mismatch gates.

### Input

Provide `urls`. `expectedKind` can be `auto`, `html`, `json`, `xml`, `text`, `image`, or `pdf`. `previousSnapshots` enables drift detection. `failRunOnMismatch` can turn the Actor into a CI gate after evidence is written. `maxUrls` bounds batch size.

### Output

Each result contains the final URL, status, score, raw Content-Type, declared kind, sniffed kind, expected kind, mismatch flag, charset, nosniff state, HTTPS state, Content-Disposition, response fingerprint, changed fields, regression state, issue codes, and an `agentAction`.

### Example

```json
{
  "urls": ["https://example.com"],
  "expectedKind": "html",
  "previousSnapshots": {},
  "failRunOnMismatch": false
}
```

### Use cases

- API response contract QA.
- CDN and reverse-proxy migration checks.
- Browser MIME-hardening reviews.
- Static asset validation.
- Technical SEO response checks.
- Scheduled response-metadata drift monitoring.

### Pricing

Billing is pay per audited URL result. The Actor uses bounded direct HTTP requests and requires no paid API or external AI model.

### Limitations

Content sniffing is intentionally heuristic and bounded; it is not a full file-format parser. Compressed, encrypted, streaming, or proprietary formats may be classified conservatively. Authenticated/private endpoints are outside scope.

### Privacy and permissions

Only bounded content from public HTTP(S) responses is inspected. Private and reserved network targets are rejected before requests are made.

#### Input reliability — 25 October 2026

Target lists are validated before network work, trimmed and deduplicated. Empty lists and malformed baselines are rejected rather than silently auditing a default website. Exact duplicate targets produce one result. Existing output fields and prices are preserved.

# Changelog

This Actor's version history is a separate document: https://apify.com/quanmatrix/content-type-charset-auditor/changelog.md

# Actor input Schema

## `urls` (type: `array`):

Configure URLs for this Actor run. Exact duplicates are processed once; empty target arrays are rejected.

## `expectedKind` (type: `string`):

Configure Expected content kind for this Actor run.

## `previousSnapshots` (type: `object`):

Configure Previous response snapshots for this Actor run.

## `failRunOnMismatch` (type: `boolean`):

Configure Fail on MIME/contract mismatch for this Actor run.

## `maxUrls` (type: `integer`):

Configure Maximum URLs for this Actor run.

## `concurrency` (type: `integer`):

Maximum URLs audited in parallel.

## `mcpConnectors` (type: `array`):

Optional MCP connectors authorized in your Apify account. Use them to send or write this Actor result to tools such as Slack, Notion, GitHub, Sentry, Supabase, or another compatible MCP service.

## `mcpToolName` (type: `string`):

Optional exact MCP tool name. Leave blank to let the selected MCP action preset discover a compatible tool automatically.

## `mcpToolArguments` (type: `object`):

JSON object passed to the selected MCP tool. String values may use {{actor_title}}, {{result_summary}}, or {{result_json}} placeholders.

## `mcpFailOnError` (type: `boolean`):

When enabled, an MCP delivery error fails the Actor run. Disabled by default so data extraction and intelligence results remain available even if the external destination is unavailable.

## `mcpActionPreset` (type: `string`):

Choose a safe action pattern. AUTO_SAFE_WRITE discovers a compatible non-destructive write tool automatically; use a specific preset for Slack, GitHub, Notion, or database delivery.

## Actor input object example

```json
{
  "urls": [
    "https://example.com"
  ],
  "expectedKind": "auto",
  "previousSnapshots": {},
  "failRunOnMismatch": false,
  "maxUrls": 100,
  "concurrency": 5,
  "mcpToolName": "",
  "mcpToolArguments": {},
  "mcpFailOnError": false,
  "mcpActionPreset": "AUTO_SAFE_WRITE"
}
```

# Actor output Schema

## `dataset` (type: `string`):

No description

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {};

// Run the Actor and wait for it to finish
const run = await client.actor("quanmatrix/content-type-charset-auditor").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = {}

# Run the Actor and wait for it to finish
run = client.actor("quanmatrix/content-type-charset-auditor").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{}' |
apify call quanmatrix/content-type-charset-auditor --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,quanmatrix/content-type-charset-auditor"
        }
    }
}
```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/a2VHNwjc9CUaEM7G4/builds/mup0CmYFF9oznwfSr/openapi.json