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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

607 articles
6 languages
12 topics
Updated Nov 11, 2026

ChatGPT checkout error box with a Retry button beside the headline Failed request, not a decline, and a reminder to check your bank or wallet first

LatestChatGPT & OpenAI

Checkout could not be completed. Please try again. ChatGPT Fix

In ChatGPT, this box means a checkout request failed, not that your bank declined the card. Check your bank or wallet for a charge before you press Retry.

Nov 11, 202611 min

Codex account/read failed during TUI bootstrap: the error tail picks the fix, with discovery failed or timed out pointing to a server restart, unauthorized (401) to a re-login on that host, and duplicate workspace to no user-side fix yet

Developer Tools & Agents

Codex workspace routing discovery failed or timed out: account/read failed during TUI bootstrap

workspace routing discovery failed or timed out clears in most reports with a background-server restart; unauthorized (401) needs a new sign-in on that host.

Nov 11, 202624 min

AI Studio permission denied toast: likely an account flag, not an IAM role, so check age, region and status, then report

API Guides

Failed to list imported projects: permission denied in AI Studio

AI Studio refused your signed-in account without naming the check. Google staff point to age, region or verification flags, not IAM roles. Check them in order.

Nov 11, 202615 min

Gemini 4 Argon scores 50.41 and Claude Fable 5.1 scores 50.02 on AA, while Fable's everyday-task bill falls from 8.6x to 4.3x Argon's

Model Comparisons

Gemini 4 Argon vs Claude Fable 5.1: A Tie on Score, Not on Cost

Gemini 4 Argon and Claude Fable 5.1 tie on Artificial Analysis, yet Fable cost 8.6x Argon on everyday tasks in an October–November test, 4.3x from December 1.

Nov 11, 202618 min

Gemini 4 Argon default passing 8 tasks for $0.096, Claude Fable 5.2 medium scoring 56 for $3.80 per task, GPT-6 Astra right on a 146 KB log in 26 s

Model Comparisons

Gemini 4 Argon vs Claude Fable 5.2 vs GPT-6 Astra: Cost per Task

Gemini 4 Argon's default passed 8 small tasks for $0.096 vs $0.41+ on the others. For hard or long exact work, start with Claude Fable 5.2 at medium.

Nov 11, 202622 min

Comparison card of Gemini 4 Argon, Claude Opus 5.5 and GPT-6.1 Sol showing their status on October 1, 2026, before Argon opened to developers on October 13

Model Comparisons

Gemini 4 Argon vs Claude Opus 5.5 vs GPT-6.1 Sol: Same-Task Test

Same tasks, one gateway: Opus 5.5 at high effort cost $0.31, Argon at high $0.40 through Nov 30 and $0.81 from Dec 1, when its token price equals Opus.

Nov 11, 202629 min

Gemini 4 Argon vs 3.8 Flash: 2.67x per token but about 1.6x per task, widening to 5.33x and 3.2x in December 2026

Model Comparisons

Gemini 4 Argon vs 3.8 Flash: Cost per Task and When to Switch

Gemini 4 Argon lists at 2.67x 3.8 Flash per token, but on five same-prompt calls it cost 1.57x as much through Nov 30, 2026, and 3.15x in December.

Nov 11, 202624 min

Gemini 4 Argon vs GPT-6 Astra: AA index 50 vs 55 at high, Argon's API price rising from $2/$10 to $4/$20 on December 1 while Astra stays at $10/$50

Model Comparisons

Gemini 4 Argon vs GPT-6 Astra: Which to Use Now and After Dec 1

GPT-6 Astra outscores Gemini 4 Argon 55 to 50 at the same high setting. Argon is cheaper at its default, but its API price doubles on December 1, 2026.

Nov 11, 202619 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: Out Nov 10 on Paid API and Ultra

Gemini 4 Carbon (gemini-4-carbon) went GA on November 10, 2026 for paid Gemini API keys and is rolling out to Google AI Ultra. $2/$10 per 1M tokens to Nov 30.

Nov 11, 202615 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, 60 to 59, but Opus still leads coding agents and office work, and Carbon's half price ends November 30.

Nov 11, 202623 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: When Slower Carbon Pays Off

Since November 10, 2026, both cost the same per token, but on identical prompts Carbon wrote 3.8x Argon's output. It pays on hard, long jobs, not quick ones.

Nov 11, 202623 min

Several Gemini API keys share one project's RPM, TPM, and RPD limits.

API Guides

Gemini API Free Tier 2026: Limits, Free Models, and Free API Keys

Gemini API keys are free, but free inference requires an eligible project, model and feature. Check live limits, grounding exceptions, 403s and data-use rules.

Nov 11, 202621 min

Gemini API access map connecting an official project key to billing, usage, and a separate provider contract

API Guides

Gemini API Pricing 2026: Token Rates, Free Tier, and Key Cost

A Gemini API key is free, but usage is free only within per-project limits. Gemini 3.8 Flash costs $0.75/$3.75 per 1M tokens; Gemini 4 Argon is paid-only at $2/$10 until Dec 1.

Nov 11, 202618 min

Cover image for a guide to Gemini API rate limits, usage tiers and spend caps

API Guides

Gemini API Rate Limits 2026: Free vs Paid Tiers and How to Raise

Gemini API rate limits (RPM, TPM, RPD) apply per project, not per key, and your live numbers are in AI Studio. Tier 2 and Tier 3 unlock at $100 and $1,000 paid.

Nov 11, 202614 min

Developer path from a controlled Google Cloud project to a protected Gemini API key and a successful first request

API Guides

Google AI Studio API Key: Is It Free? Create, Secure, Verify

The Gemini API key from Google AI Studio is free. Flash, Flash-Lite and 2.5 Pro calls are free within project limits; image models and 3.1 Pro need billing.

Nov 11, 202610 min

Gemini API key and project inheriting billing plan, tier, caps, and service state from a Cloud Billing account

API Pricing & Plans

Gemini API Billing Tiers: Prepay vs Postpay and No Credits Fixes

As of October 10, 2026, paid Gemini API usage runs on Prepay credits. Postpay accounts must switch by their notice date; a $0 balance returns HTTP 402.

Nov 11, 202615 min

GPT-6.1 Sol not showing: listed in ChatGPT Work on the web but missing from the Codex /model picker, pointing to six local client causes

Troubleshooting

The 'gpt-6.1-sol' model is not supported when using Codex with a ChatGPT account — GPT-6.1 Sol Not Showing in Codex or ChatGPT

The error doesn't prove your plan is excluded: on one Pro account, Codex CLI 0.158.0 got it and 0.159.0 worked. Check the ID, client, daemon, then the account.

Nov 11, 202627 min

Kimi K3.1 Pro and Gemini 4 Argon both at $2 input and $10 output per million tokens through November 30, 2026, with Argon at $4 and $20 from December 1

Model Comparisons

Kimi K3.1 Pro vs Gemini 4 Argon: Same Price Only Until Dec 1

Both list at $2/$10 per 1M tokens through November 30, 2026, then Argon doubles. K3.1 Pro leads terminal coding; Argon leads overall and on factual recall.

Nov 11, 202617 min

Nano Banana 2 limits guide showing the Gemini app's 5-hour compute-based usage limit next to the per-project API rate-limit tiers

AI Image Generation

Nano Banana 2 Limits: How Gemini Usage and API Rate Limits Work

As of November 2, 2026, Flow caps Nano Banana 2.1 and 2 Lite at 400 images a day, 1,000 on a plan; the Gemini app has 5-hour and weekly limits, no image count.

Nov 11, 202629 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.

Nov 11, 202617 min

Decision map separating Nano Banana Pro limits in personal Gemini, AI Mode, Workspace, Flow and the Gemini API

AI Image Generation

Nano Banana Pro Limits: Gemini, AI Mode, Workspace and API Quotas

No single Nano Banana Pro daily limit: Flow caps Pro at 20–500 images a day by plan, the Gemini app refreshes every 5 hours, AI Mode and Workspace reset daily.

Nov 11, 202621 min

An unsupported-role error is repaired by routing instructions to the appropriate API surface while preserving authority, timing, and tool pairs.

Troubleshooting

Fix API 400 Unsupported Role Errors Without Breaking System Prompts

Start with the final outbound request. Use the instruction field and message positions supported by that exact endpoint, preserve tool-call pairs, and verify the full task after the role error clears.

Nov 10, 202612 min

Illustrated cover for AWS Claude 400 errors: a developer at a laptop, a magnifier over an HTTP 400 invalid_request_error card, and notes for error message, endpoint and model

Troubleshooting

AWS Bedrock Claude 400 Error: Match the Exact Message to the Fix

A Claude 400 on Amazon Bedrock can be a stripped beta header, old Claude Code, full context, a bad model ID or an account setting. Fix it by the exact message.

Nov 10, 202615 min

Cheapest AI API by token mix: GPT-6 Luna at $0.10 / $0.50, DeepSeek Flash cached input at $0.003 off-peak, and Grok 4.7 at $2 / $6 per 1M tokens

API Pricing & Plans

AI API Price Comparison: Cheapest Model by Input and Output Mix

As of September 26, 2026, GPT-6 Luna and DeepSeek Flash cost least per token. Among $2-input models, Grok 4.7 is cheapest; past 272K tokens, Sonnet 5 beats Sol.

Nov 10, 202618 min