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  • Added permanent redirects from /api-authentication to Authentication and from /error-handling to Error Handling, so older links reach the current guides.
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Documentation discovery for AI tools

  • Added a product summary and task-routing guidance to the automatically generated documentation index, Markdown pages and full-text documentation.
  • Reorganized the website text index around student writing, published tests, apps and agent workflows, with links to the full documentation export, detector records and sitemaps.
  • Added dated USD web-plan prices and allowances, annual charges, weekly options and separate API plan facts to the website index. The API pricing summary now includes Build, Grow and Scale prices and included plan words in the generated documentation index.
  • Refreshed the API introduction with direct routes for humanization, writing, async and bulk jobs, explicit text preservation, MCP setup and detection, plus billing, data-handling and published-output references.
  • Made the model and workflow summaries more specific so AI tools can identify the right reference from the index.
  • Clarified Super and Standard’s rewrite descriptions and linked the published model comparison for the specific observed outputs and detector results.
This is a documentation-discovery update. API endpoints, authentication, request and response contracts, models and prices are unchanged. The index and full-text export remain automatically generated from the documentation.
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Developer guides and integration updates

New guides cover repeatable humanization workflows from a script, publishing queue or coding agent.

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What’s New

  • TypeScript and Python review recipes: submit single async runs or batches of up to 100, resume saved run IDs, retry with stable keys, verify signed webhooks and collect results for editorial review. Includes billing guidance and a sample drafts download.
  • Codex MCP guide: connect through OAuth, call humanize_text and retrieve the completed result with get_run_status. The guide records the setup and workflow verified on November 7.
  • API data-handling guide: documented request and result history, processing roles, async callbacks, retention-policy contacts and integration planning.

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Documentation Updates

  • MCP model selection: clarified the existing super default, explicit standard and lite selection, the REST account-based model requirement and the deprecated heavy alias.
  • Workflow patterns and code examples now link to the new review recipes, with a dedicated Recipes section in navigation and client-specific MCP setup guidance.
  • n8n integration guide: aligned model choices and terminal error behavior with published node version 0.1.2, and added HTTP Request guidance for Super and bulk jobs.
  • Website text index: refreshed links to current API and agent guides, review recipes, data handling, comparisons and published evidence.
  • MCP setup and verification: added a dated client matrix, aligned the website’s Codex guidance and localized billing descriptions, distinguished ChatGPT setup from completed verification, and clarified the available MCP tools, separate REST detection endpoint and bearer-token setup steps.
  • MCP benchmark evidence: linked Super’s scoped October 2026 HumanizerEval results from the MCP buyer FAQs.
  • Pricing reference: removed a duplicate page heading while preserving prices and word-accounting formulas.
The API landing page also links the developer comparison, runnable recipes and StudySim case study. Its author metadata now identifies StealthGPT consistently.The recipes were checked against the API source and exercised with local fixtures and mocked responses. This entry covers documentation additions and clarifications.
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Bulk async runs

Queue up to 100 writer or humanizer runs in one request. Each item becomes its own async run with its own runId, status and webhook.

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What’s New

  • POST /api/stealthify/runs/bulk: an items array, each item a POST /api/stealthify/runs JSON body
  • items[].idempotencyKey: sending an item again with its key returns the run it already started
  • One billing check for the batch: if your balance or pay-as-you-go can’t cover the estimate for every item, nothing is queued
  • One batch at a time per account: a new bulk request while the last one is still running gets 409
  • Works with preservation and with rephrase: false prompts, like single runs

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Where to Start

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API plans

API access now starts with a monthly API plan. Each plan includes a set number of words per billing period, and usage beyond them is billed pay-as-you-go.

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What’s New

  • Build, Grow and Scale: $19/month for 100,000 words, $49/month for 275,000 words, or $99/month for 600,000 words
  • Plan words refresh every billing period: unused plan words don’t roll over
  • Plan words by model: Super uses 2.5 plan words per charged word; standard, lite and /api/stealthify/detect use one
  • Pay-as-you-go turns on with your first plan payment: there is no separate card setup step
  • Pay-as-you-go rates are unchanged: $0.20 / 1,000 words for standard and lite, $0.05 / 100 words for Super
  • MCP enable_pay_as_you_go: returns plan_required with a pricingUrl for accounts without an API plan

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Who’s Affected

  • New API accounts: choose a plan at stealthgpt.ai/stealthapi to activate API access
  • Accounts with pay-as-you-go already on: keep it, no action needed

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Where to Start

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Text preservation

Mark the spans that must not change, such as links, HTML tags or headings, and send preservation: true. The text around them is humanized and every marker comes back byte-for-byte, in the same order.

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What’s New

  • preservation on POST /api/stealthify and POST /api/stealthify/runs, off by default
  • preservationOpen, preservationClose, preservationMaxLookahead: change the [[ + up to 10 characters + ]] marker rule
  • preservationMode: inline (default) or split
  • preservation in the response: marker counts, the mode used, and whether the text fell back to split
  • super rewrites the whole text in one pass without the markers, then every marker is put back from your input
  • Words inside markers are not billed
  • prompt on POST /api/stealthify/runs: same as text, the name POST /api/stealthify uses

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Where to Start

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AI Detector document limit

POST /api/stealthify/detect now accepts documents up to 50,000 characters. The previous cap was 3,000 words.

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Where to Start

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Writer mode on async runs

POST /api/stealthify/runs can generate content the same way as the synchronous writer, then humanize the draft.

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What’s New

  • rephrase: true (default) humanizes text. false writes from text, then humanizes the draft
  • tone and writingMode: same writer controls as POST /api/stealthify, used only when rephrase is false
  • writingMode default is default: omitted writingMode follows the prompt on both POST /api/stealthify and POST /api/stealthify/runs. Send "writingMode": "essay" to keep the academic essay structure
  • Existing clients: requests that omit rephrase still humanize

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Where to Start

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Introducing Super

The flagship Super humanizer is available on the Writer & Humanizer API. heavy is deprecated and now routes to standard. Standard and lite pricing drops to $0.10 / 1,000 words. Super is billed at $0.05 / 100 words.

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What’s New

  • super model: flagship next-gen humanizer on POST /api/stealthify, POST /api/stealthify/runs, and the MCP humanize_text tool
  • heavy is deprecated: model: "heavy" is accepted as an alias of standard
  • Pricing: standard and lite are $0.10 / 1,000 words; Super is $0.05 / 100 words

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Where to Start

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Standard Humanizer Model

The previous-generation full rewrite is available again as model: "standard" on the Writer & Humanizer API.

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What’s New

  • standard model: previous-generation full rewrite, using the earlier humanizer pipeline
  • Available on: POST /api/stealthify, POST /api/stealthify/runs, and the MCP humanize_text tool
  • Default unchanged: requests that omit model still use heavy

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Where to Start

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Automatic Claude Watermark Removal During Humanization

Humanization now strips invisible Claude and Gemini text watermarks automatically. A text watermark is not a logo on the page, it is a statistical pattern baked into the model’s word choices, invisible to a reader, and it can travel with copy and paste. Claude and Gemini (via SynthID) both mark output this way. Light edits often leave the signal intact. A structural rewrite at the sentence level is the category of change those marks are not built to survive, and that is what the humanizer already does.

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What’s New

  • Automatic on every humanize: Claude, Gemini SynthID, and other invisible text watermarks are stripped as part of the rewrite, no extra step or parameter
  • Sentence-level rewrite, not a synonym swap: meaning stays intact; the mark does not survive
  • Applies across humanizer surfaces: POST /api/stealthify (rephrase: true), POST /api/stealthify/runs, and the humanize stage of Stealth Agent

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Where to Start

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Humanize PDF & DOCX Files

POST /api/stealthify/runs now accepts file uploads. Send a document as multipart/form-data and the text is extracted server-side, then humanized like a regular text run — the result is returned as plain text in the usual result field.

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What’s New

  • File upload on the async endpoint: send multipart/form-data with a file field instead of a JSON text body
  • Supported types: .pdf, .docx, .txt, .md (max 4MB; scanned or image-only documents are not supported)
  • Same options: qualityMode, model, outputFormat, webhookUrl, and webhookSecret can be passed as form fields
  • Same billing: file runs use the same per-word rates as text runs

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Compatibility

JSON requests to POST /api/stealthify/runs are unchanged. The legacy POST /api/stealthify endpoint is unaffected.

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Where to Start

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Zapier Integration (Live)

The StealthGPT Zapier integration is now live. Connect StealthGPT to 8,000+ apps and generate or humanize content inside your Zaps — no code required.

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What’s New

  • Live on Zapier: add StealthGPT from App Connections → Create connection
  • Bring your own API token from your Stealth API dashboard
  • Actions for Generate Long-Form Content, Humanize Text, and Get Run Status — built on the async API

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Where to Start

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WordPress Plugin (Live)

The official StealthGPT WordPress plugin is now available on the WordPress.org directory. Generate long-form content or humanize existing text directly in WordPress — the result lands in a draft post for review before publishing.

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What’s New

  • Live on WordPress.org: install from Plugins → Add New → search “StealthGPT”
  • Bring your own API key; full generation and humanization, both written to drafts
  • Async by design — runs complete via webhook with background polling fallback

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Where to Start

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More Integrations: Zapier & WordPress (in review)

Two more integrations are built and currently in review on their respective marketplaces:
  • Zapier app — Generate Long-Form Content, Humanize Text, and Get Run Status across 7,000+ apps. In review by Zapier.
  • WordPress plugin — generate or humanize content into draft posts, BYO API key. In review for the WordPress.org directory.
Until they’re live, automate StealthGPT via the n8n node, MCP clients, or the async REST API.

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Where to Start

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n8n Node (Verified)

StealthGPT is now an official, n8n-verified node, n8n-nodes-stealthgpt — listed on the n8n integrations directory. Start content-pipeline runs and humanize text directly inside n8n workflows, using the async API under the hood.

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What’s New

  • Verified by n8n: available on self-hosted and n8n Cloud (instance owner enables once)
  • Operations: Content Generation and Text Humanization, each with Start Run and Get Run Status
  • Wait for completion: start-and-wait (poll until terminal) or start-only for webhook/manual polling

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Where to Start

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MCP Server + OAuth

StealthGPT now ships a remote MCP (Model Context Protocol) server, so AI agents and MCP-aware clients can generate and humanize content as a tool. Connect it in Cursor, Claude Desktop/Code, and as a one-click custom connector in claude.ai (web).

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What’s New

  • MCP endpoint: https://www.stealthgpt.ai/api/mcp/mcp (Streamable HTTP)
  • Tools: generate_content, humanize_text, get_run_status
  • Dual auth: OAuth 2.1 (one-click sign-in for claude.ai web) or Authorization: Bearer YOUR_API_TOKEN (Cursor, VS Code, Claude Desktop, CLIs) — both resolve to the same account
  • Async by design: tools return a runId; poll get_run_status until terminal

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Where to Start

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Async Writer & Humanizer Runs

Writer & Humanizer now supports native async runs for long-running humanization. Create a run with POST /api/stealthify/runs, poll GET /api/stealthify/runs/{runId}, and optionally receive a terminal webhook callback through webhookUrl.

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What’s New

  • New create endpoint: POST /api/stealthify/runs
  • New polling endpoint: GET /api/stealthify/runs/{runId}
  • Idempotent create retries: send idempotency-key to avoid duplicate queued runs
  • Webhook callbacks: receive completed, failed, or cancelled payloads at webhookUrl

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Compatibility

The existing POST /api/stealthify endpoint is unchanged and remains supported for current API clients.

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Where to Start

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Async Stealth Agent Runs

Stealth Agent now supports native async runs for long-running integrations. Create a run with POST /api/stealthify/agent/runs, poll GET /api/stealthify/agent/runs/{runId}, and optionally receive a terminal webhook callback through webhookUrl.

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What’s New

  • New create endpoint: POST /api/stealthify/agent/runs
  • New polling endpoint: GET /api/stealthify/agent/runs/{runId}
  • Idempotent create retries: send idempotency-key to avoid duplicate queued runs
  • Webhook callbacks: receive completed, failed, or cancelled payloads at webhookUrl

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Where to Start

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AI Detector Endpoint

A new POST /api/stealthify/detect endpoint exposes the same AI-detection backend that powers the AI Detector tool on the website. Submit text and receive a howLikelyToBeDetected score (0-100) using the standard Stealth API authentication and billing model.

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What’s New

  • New endpoint: POST /api/stealthify/detect
  • Request body: { "text": string } (max 3,000 words)
  • Response: howLikelyToBeDetected (0-100), wordsSpent, remainingCredits, billingMode, meteredChargedCredits
  • Billing: charged words = input words (1 charged word per input word)

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Where to Start

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Business Mode Removed, Replaced by Stealth Agent

Business mode on /api/stealthify has been removed and replaced by the new Stealth Agent endpoint. Stealth Agent runs a full pipeline (research → draft → optional fact-check → humanize → optional images) in a single call, producing higher-quality long-form output than the previous Business engine.

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What’s Changed

  • business flag removed: The 10x business engine no longer runs. The business field is still accepted in /api/stealthify request bodies for backward compatibility but has no effect — no client changes are required.
  • Billing simplified: All /api/stealthify requests are billed at the standard rate. The 10x business multiplier no longer applies.
  • Migration path: Workloads that previously relied on Business mode (academic, SEO long-form, professional posts) should switch to POST /api/stealthify/agent.

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Where to Start

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Business Mode Temporarily Disabled

Business mode on /api/stealthify is currently disabled.

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What’s Changed

  • business flag ignored: Requests are processed with the standard engine regardless of whether business is sent as true or false
  • Standard billing applied: All /api/stealthify usage is billed at the standard rate, with no 10x Business multiplier
  • Schema unchanged: The business field is still accepted in request bodies for backward compatibility; no client changes are required
See the Writer & Humanizer endpoint, Advanced Usage, and Pricing pages for details.
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Stealth Agent API

Documentation is available for POST /api/stealthify/agent: multi-step Stealth Agent generation (academic, SEO, or social) with the same Stealth API authentication and billing model as /api/stealthify. See Stealth Agent.
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Free-to-Start API Billing

StealthGPT API billing has moved to a free-to-start pay-as-you-go model.

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What’s Changed

  • Free activation flow: New users now activate API billing by adding a payment method instead of buying a fixed starter pack
  • Usage-based invoicing: API usage is billed automatically as pay-as-you-go
  • Tiered billing thresholds: Invoicing thresholds now scale by tier based on spend within each billing period
  • Automatic tier advancement: Accounts can move up to higher invoice thresholds automatically as billing-period spend increases; for higher limits or custom arrangements, email joey@stealthgpt.ai

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Impact for Existing Users

  • Users with prepaid words: Existing balances continue to be used first with no interruption
  • Legacy users: If prompted, accept updated billing terms in the dashboard to keep uninterrupted API access
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Pay-As-You-Go Billing Enabled

StealthGPT API now supports pay-as-you-go billing after your starter/prepaid words are used.

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What’s New

  • Hybrid Billing Model: Start with free starter access after activation/payment setup (and/or prepaid words), then continue automatically on usage-based billing
  • Standard Usage Rate: $0.20 per 1,000 words for standard requests (business=false)
  • Business Usage Rate: $2.00 per 1,000 words for business requests (business=true)
  • Legacy Account Action Required: Legacy users must accept the new terms in their billing dashboard to continue billing under the updated model

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How It Works

After your prepaid word balance reaches zero, requests continue without interruption and usage is billed automatically based on endpoint mode and word consumption.
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New Detector Optimization

You can now optimize your content for specific AI detection tools using the new detector parameter.

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What’s New

  • Detector Parameter: Choose between "turnitin" (default) or "gptzero" to optimize your content for different detection systems
  • Automatic Optimization: The API automatically adjusts generation settings based on your selected detector
  • Enhanced Compatibility: Improved performance across different AI detection platforms

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Getting Started

Simply add the detector parameter to your /api/stealthify requests to get content optimized for your preferred detection tool.
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Tokens Deprecated, Words Introduced

The StealthGPT API now uses a word-based system instead of tokens. All references to tokens have been replaced with words throughout the documentation and API responses.

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Deprecated Fields in /api/stealthify

  • tokensSpent (use wordsSpent instead)
  • systemTokensSpent
  • totalTokensSpent

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New Field

  • wordsSpent (number of words used for content generation or rephrasing)