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AI Model & API Guides

Source-linked guidance for AI models, API integration, and developer workflows—turning fast-changing prices, quotas, capabilities, and limits into decisions you can verify.

Primary sources first
Reproducible steps and failure boundaries
Volatile facts carry review dates

558 articles
6 languages
12 topics
Updated Oct 30, 2026

Guide to the 2026 ChatGPT student offer covering eligibility, verification, billing, and renewal

LatestChatGPT & OpenAI

ChatGPT Student Discount 2026: Who Gets 4 Free Months of Plus

Eligible U.S. college students get four free months of ChatGPT Plus, then $20 a month. It includes GPT-6 Astra in ChatGPT Work and Codex, but not ChatGPT Pro.

Oct 30, 20269 min

Claude Code

Claude Code 403 "Your Account Can't Receive Replies": Next Step

It's an Anthropic identity check, not a bug; retries won't clear it. Verify at portal.anthropic.com if you're in a supported country with a physical photo ID.

Oct 30, 202610 min

Claude Code

Claude Code Cache TTL and Token Usage: Why Cache Misses Get Expensive and How to Prove It

Claude Code cache TTL is route-specific. Check the active route, TTL, cache creation tokens, cache read tokens, invalidators, and billing proof before blaming a bug.

Oct 30, 202613 min

Claude prompt caching: cache reads at 0.05x input on Opus and Sonnet 5.5, a 5-minute or 1-hour lifetime and a 512-token minimum prefix

API Guides

Claude Prompt Caching: How It Works, Costs, 512-Token Minimum

Mark a stable prefix with cache_control and Claude reuses it for 5 minutes or 1 hour. Reads cost 0.05x input on Opus and Sonnet 5.5; prefixes need 512+ tokens.

Oct 30, 202619 min

Claude structured output: a JSON schema in output_config.format returns a JSON string in the text block, followed by a stop_reason check and local validation with Pydantic or Zod

API Guides

Claude Structured Output: JSON Schema Guide and What Still Fails

Put a JSON schema in output_config.format and Claude returns matching JSON in the text block. Still check stop_reason and validate ranges and lengths yourself.

Oct 30, 202612 min

The Claude tool-use limit for this turn banner with its Continue button, beside cards showing one reply's tool calls ran out and no reset time is shown

Troubleshooting

Claude Reached Its Tool-Use Limit for This Turn: What to Do

One Claude reply ran out of tool calls; it isn't your 5-hour or weekly limit. Click Continue, then check what actually ran before trusting the summary.

Oct 30, 202610 min

Two Codex Browser disabled messages compared: the in-chat Work settings message fixed by a full quit and new chat, and the Settings → Browser message traced through the log reason

Troubleshooting

Codex Browser Disabled Even When Enabled: 2 Messages, 2 Fixes

Browser on but Codex says it is disabled? Fully quit and reopen the ChatGPT app, continue in a new chat, then check Work preferences → Local browser use.

Oct 30, 202614 min

DeepSeek Search API pricing: $0.00075 per successful request, about $0.002 per Claude Code search on deepseek-flash, and agent search billing from October 31, 16:00 UTC

API Pricing & Plans

DeepSeek Search API Pricing: $0.75/1K and Real Cost per Search

DeepSeek Search and Fetch: $0.75 per 1,000 successful requests, empty results free. Claude Code and Codex searches are billed from Oct 31, 2026, 16:00 UTC.

Oct 30, 202614 min

Gemini 4 Carbon vs Argon: Carbon's lead ranges from +14.9 on FrontierCode 2.0 to +0.3 on AutomationBench-AA

Model Comparisons

Gemini 4 Carbon vs Gemini 4 Argon: Slower Start, Faster Agents

Gemini 4 Carbon beats Argon 59.4 to 50.4 on AA's index but ties on SaaS automation. It's twice as slow to start a reply, yet finishes coding-agent tasks faster.

Oct 30, 202615 min

Gemini API error troubleshooting: deciding whether a 429 RESOURCE_EXHAUSTED should be retried or fixed

API Guides

Gemini API Error Troubleshooting: 429 RESOURCE_EXHAUSTED, 400/500

A Gemini 429 RESOURCE_EXHAUSTED can be a per-minute limit, a daily quota, a spend cap or no quota for the model. The error body says whether to retry or stop.

Oct 30, 202617 min

Claude Code

GLM-5.3-Flash in Claude Code: Setup That Actually Runs Flash

Point Claude Code at Z.ai's Coding Plan endpoint and put glm-5.3-flash[1m] in the Opus slot, which runs the main session. Effort defaults to high, not max.

Oct 30, 202616 min

Codex Usage dashboard with separate five-hour and weekly windows plus wait, reset, credits, and API paths

Developer Tools & Agents

Codex Weekly Limit Reset: Find Your Time or Reset Now

Codex has no fixed reset day. Tibo's 28-day campaign has brought four global resets as of October 20, 2026; Settings → Usage shows whether one reached you.

Oct 30, 202622 min

OpenAI versus Claude cache pricing board showing cached input, cache writes, cache reads, TTL, and usage field verification

API Guides

OpenAI vs Claude Cache Pricing: How Cached Tokens, Cache Writes, and Cache Reads Are Billed

OpenAI cache hits are cached input tokens; Claude separates cache writes and reads. Use this dated guide to audit repeated-context API and agent bills.

Oct 30, 202611 min

Qwen Image 3.0 in ComfyUI: a Partner Node sends each job through Comfy's API to Alibaba's servers, no GPU or model file needed

AI Image Generation

Qwen Image 3.0 in ComfyUI: No Download, Setup, and Cost per Image

There are no Qwen Image 3.0 weights to download. ComfyUI runs it through two paid Partner Nodes: $0.0429 per standard image, Pro $0.0572 or $0.10725 by size.

Oct 30, 202617 min

GPT-6.1 Terra not in Codex: CC Switch Routing returns an empty list, the bundled list has Terra from 0.165.0, and Direct mode lists it

Troubleshooting

GPT-6.1 Terra Not Showing in Codex With CC Switch: Fix by Mode

In CC Switch Routing mode, Codex gets an empty model list and shows its bundled one, which has GPT-6.1 Terra only from 0.165.0. Go back to Direct and restart.

Oct 29, 202612 min

Gemini 4 Carbon status on October 29, 2026: rolling out to Fairwind cyber defenders only, not yet in the Gemini API, AI Studio, Gemini app, Vertex AI or Antigravity

API Pricing & Plans

Gemini 4 Carbon Release Date: Cyber Defenders Only for Now

Google announced Gemini 4 Carbon on October 28, 2026, but only Fairwind cyber defenders can use it. No public API or app date yet; build on Argon meanwhile.

Oct 29, 202611 min

Gemini 4 Carbon vs Claude Opus 5.5: Carbon leads the AA index 59.4 to 58.4, Opus leads coding agents and costs less per task at xhigh

Claude Code

Gemini 4 Carbon vs Opus 5.5: Opus Still Wins Coding Agents

Gemini 4 Carbon edges Claude Opus 5.5 on AA's index, 59.4 to 58.4, but Opus still leads coding agents and office work, and it is the one you can call today.

Oct 29, 202616 min

Two Gemini API requests side by side: contents ending on a model turn return 400 INVALID_ARGUMENT, and the same chat ending on the next user turn returns 200

API Guides

Gemini "Requests ending with a model turn are not supported" Fix

Gemini 3.6 Flash and later, including Gemini 4 Argon, reject any request whose last turn is model (assistant). End contents on a user turn to fix the 400.

Oct 29, 202611 min

GPT Image 2 API pricing: $0.005 to $0.43 per image on OpenAI Standard, half the rate on Batch, $0.03 flat per call

API Pricing & Plans

GPT Image 2 API Pricing: Cost per Image, Batch, and $0.03 Calls

GPT Image 2 costs about $0.005 to $0.43 per image in output on OpenAI's API, set by size and quality. Batch halves it, and ChatGPT has no per-image price.

Oct 29, 202612 min

GPT Image 2 and 2.5 4K price per image as of October 29, 2026: about $0.40 on OpenAI, $0.08 on Kie.ai and UnificAlly, $0.03 flat on LaoZhang API -vip

AI Image Generation

Cheapest Real 4K GPT Image 2 / 2.5 API: $0.03 Native, Tested

As of October 29, 2026, $0.03 per image on LaoZhang API is the lowest price found for native 4K GPT Image 2 and 2.5, at every quality tier, edits included.

Oct 29, 202610 min

Conceptual Nano Banana Pro 4K workstation with image size configuration, crop framing and print workflow

AI Image Generation

Nano Banana Pro 4K: Exact Sizes, $0.24 Cost and Watermark Rules

Nano Banana Pro gives 4K only when you ask for it: 16:9 is 5504x3072. Google charges $0.24 per 4K image, $0.12 on Batch; LaoZhang API $0.09 at any size.

Oct 29, 202624 min

Three separate Nano Banana Pro invoices for Google API usage, a Google AI Pro membership, and an independent provider call

AI Image Generation

How Much Is Nano Banana Pro? API, Plan, and Usable-Image Cost

Nano Banana Pro is $0.134 per 1K/2K image and $0.24 at 4K on Google's API; Google AI Pro is $19.99 a month with no API. LaoZhang API: $0.09 a call at any size.

Oct 29, 202617 min

Claude Haiku 5.5 vs GPT-6 Luna: the same $0.10/$0.50 rate card up to 100K tokens, but $0.047 vs $0.017 per task, 2.7x, at medium effort (AA v4.3.2)

Model Comparisons

Claude Haiku 5.5 vs GPT-6 Luna: Same Price, 2.2x Cost per Task

Claude Haiku 5.5 and GPT-6 Luna share $0.10/$0.50 rates under 100K tokens, yet Haiku cost 2.2x more per task at default effort and reprices 5x above 100K.

Oct 28, 202620 min

Claude Haiku 5.5 vs Sonnet 5.5: a 20x per-token price gap up to 100K-token prompts, 4x above it, and 39.2% vs 70.6% on Terminal-Bench 4.0

Claude Code

Claude Haiku 5.5 vs Sonnet 5.5: When the 20x Price Gap Pays Off

Claude Haiku 5.5 costs 1/20 of Sonnet 5.5 per input and output token but trails it on agentic coding. Move checkable work to Haiku; keep agents on Sonnet.

Oct 28, 202616 min