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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.

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545 articles
6 languages
12 topics
Updated Oct 28, 2026

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)

LatestModel 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

Claude Opus 5.5 vs GPT-6.1 Terra: 1/9 the cost at max effort, 3.6x per task at matched scores, about 5.8x on English input

Model Comparisons

Claude Opus 5.5 vs GPT-6.1 Terra: 1/9 the Cost Only at Max

GPT-6.1 Terra's 1/9 cost claim is max vs max. At equal AA scores, Opus 5.5 high costs 3.6x Terra max per task, and English input bills about 5.8x.

Oct 28, 202616 min

Claude Opus 5.5 vs GPT-6.1 Sol cover: 2x list rate up to 272K input, 4.2 to 8.9x measured cost per task, index score 51 vs 48 at medium effort

Model Comparisons

Claude Opus 5.5 vs GPT-6.1 Sol and GPT-6 Sol: When Opus Pays Off

Against GPT-6.1 Sol, Opus 5.5 costs exactly 2x per token under 272K input and stays pricier above. Opus scores higher; pay only where it passes more tasks.

Oct 28, 202615 min

Claude Sonnet 5.5 vs Sonnet 5: same $2/$10 token price, $1.12 vs $1.79 per task at high effort and $7.67 vs $5.09 at max (AA v4.3.2)

Claude Code

Claude Sonnet 5.5 vs Sonnet 5: Cost by Effort and What Breaks

Sonnet 5.5 keeps Sonnet 5's $2/$10 token prices. In Artificial Analysis's October 5 tests it cost less per task from low to xhigh and about 51% more at max.

Oct 28, 202619 min

Sonnet 5.5 vs GPT-6.1 Sol: Sonnet's cost is 1.0x Sol's per token, 1.45x per text, 2.2–7.9x per AA task and 0.72x on a 280K prompt

Model Comparisons

Claude Sonnet 5.5 vs GPT-6.1 Sol: Same Price, 2–8x Cost per Task

Same $2/$10 list price, but Sonnet 5.5 costs 2.2–7.9x GPT-6.1 Sol per AA task. Start on Sol; use Sonnet for terminal agents and prompts over 272K tokens.

Oct 28, 202620 min

Claude Sonnet 5.5 vs GPT-6 Astra cover comparing list prices of $2 and $10 against $10 and $50 per million tokens, with earlier max-effort scores of 56 and 53 and costs per task of $7.60 and $3.26 (AA v4.3.2)

Model Comparisons

Claude Sonnet 5.5 vs GPT-6 Astra: When the Cheaper Model Wins

GPT-6 Astra outscores Sonnet 5.5 at every effort level on Artificial Analysis' index. Sonnet is cheaper per task up to high, faster, and wins above 272K input.

Oct 28, 202618 min

Claude Sonnet 5.5 vs Opus 5.5: $2/$10 against $4/$20 per million tokens, with the earlier same $0.20 cache read and higher cost per task at max effort (AA v4.3.2)

Model Comparisons

Claude Sonnet 5.5 vs Opus 5.5: When Half the Price Really Saves

Sonnet 5.5 costs half as much per token and suits well-scoped work at low or medium effort. At max it costs as much per task as Opus 5.5 and scores lower.

Oct 28, 202619 min

Gemini 4 Argon finish_reason cover: a 65,536-token per-request cap, resend with the token on CONTINUATION, and a 32,768+ budget for empty MAX_TOKENS replies

API Guides

Gemini 4 Argon API finish_reason: CONTINUATION and Empty Replies

Gemini 4 Argon: resend with continuationToken on CONTINUATION, raise the budget when MAX_TOKENS has no text. OpenAI-compatible endpoints can't continue.

Oct 28, 202613 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: Cost and Access

Gemini 4 Argon opened to paid API users on October 13 at $2/$10, doubling December 1. At matched effort it costs more per task than Opus 5.5 and 6.5x GPT-6.1 Sol.

Oct 28, 202618 min

Access cards dated October 6, 2026: Fable 5.5 unannounced, Gemini 4 Argon then limited to Fairwind, GPT-6.1 Sol available, and GPT-6.1 Astra canceled.

Model Comparisons

Fable 5.5 vs Gemini 4 vs GPT-6.1: Which Can You Use Today?

As of October 14, 2026, you can call GPT-6.1 Sol and Gemini 4 Argon, available since October 13. Fable 5.5 is unannounced, and GPT-6.1 Astra was shelved.

Oct 28, 202615 min

Workload decision board comparing GPT-6 Astra and Claude Fable 5.1 across access, API cost, data rules, and acceptance testing

Model Comparisons

GPT-6 Astra vs Claude Fable 5.1: Same Price, 1.5x the Tokens

Both list at $10/$50 per million tokens, but on October 26, 2026 Fable 5.1 counted 1.45x Astra's tokens for English and cost 1.5–1.6x on tasks both passed.

Oct 28, 202618 min

GPT-6.1 Sol vs GPT-6 Astra cover: GPT-6 Sol and GPT-6.1 Sol both at $2 input and $10 output per 1M tokens, Astra at $10 and $50

Model Comparisons

GPT-6.1 Sol vs GPT-6 Astra vs GPT-6 Sol: When Astra Is Worth It

Move gpt-6-sol traffic to GPT-6.1 Sol at the same price. Astra leads it by 2–8 points at equal effort; Sol max ties Astra high for 2.6x less per task.

Oct 28, 202620 min

GPT-6.1 Terra at $1 / $5 vs GPT-6.1 Sol at $2 / $10 per 1M tokens: half the price per token, not always cheaper per task

Model Comparisons

GPT-6.1 Terra vs GPT-6.1 Sol: Half the Price, Not Always Cheaper

Terra's API and Codex rates are half of Sol's, and it ran small Codex tasks twice as fast. At xhigh effort, though, it costs more per task than Sol at medium.

Oct 28, 202619 min

GPT-6.1 Terra vs GPT-6 Luna: 10× the price per token, 2.7–6.3× the cost per passed task, and 16 vs 12 of 16 calls passed

Model Comparisons

GPT-6.1 Terra vs GPT-6 Luna: 10× per Token, 2.7–6.3× per Task

GPT-6.1 Terra costs 10× GPT-6 Luna per token. On 12 tasks tested October 28, 2026, it cost 2.7–6.3× as much per passed task and passed 15–16 of 16 to Luna's 12.

Oct 28, 202615 min

Four model cards: Sol, Luna, and Astra in the GPT-6 lineup alongside GPT-5.6 Terra

Model Comparisons

GPT-6 Sol vs Terra vs Luna vs Astra: Which Model Should You Use?

GPT-6 now has a Terra: GPT-6.1 Terra, released October 26, 2026, costs half of GPT-6.1 Sol per token and about 10 times Luna. Pick by workload, then test.

Oct 28, 202616 min

Gemini 4 Argon Retrying 1/9 in Antigravity: a large file edit goes silent for 60 s, nine attempts follow, and the fix is line ranges of up to 100 lines

Troubleshooting

Gemini 4 Argon "Retrying (1/9)": Why Large Edits Fail at 60s

Gemini 4 Argon's "Model unavailable, retrying (attempt 1/9)" in Antigravity usually means a big file edit sat silent for 60 s. Stop and edit by line range.

Oct 27, 202614 min

ChatGPT access troubleshooting across service status, browser checks, managed networks, location and account issues.

ChatGPT & OpenAI

ChatGPT Unblocked at School, Work or Abroad: Find the Block

Start with the exact error and OpenAI's status page. Then check whether the problem follows a browser, network or account; school and work restrictions need the responsible administrator.

Oct 27, 202612 min

Gemini 4 Argon usage limits: a matrix of the Gemini app, AI Mode, Antigravity, AI Studio plan quota and the paid API across Free or Plus, Pro and Ultra

Gemini & Google AI

Gemini 4 Argon Usage Limits: Pro vs Ultra, Resets, API Credits

Google AI Pro and Ultra both include Gemini 4 Argon in AI Studio, with higher daily quota on Ultra. Gemini app limits use five-hour and weekly windows; API billing is separate.

Oct 27, 202616 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.

Oct 27, 202621 min

Claude vs OpenAI API pricing: Sol matches Sonnet 5 and Astra matches Fable 5.1, Claude costs less past 272K input and on top-tier cache hits, OpenAI's Luna costs less at the budget tier

API Pricing & Plans

Claude API vs OpenAI API Pricing: When Each One Costs Less

As of September 26, 2026, GPT-6 Sol matches Sonnet 5 and Astra matches Fable 5.1 on list price. Prompts over 272K favor Claude; Luna costs a tenth of Haiku 4.5.

Oct 26, 202611 min

Decision map from the August 2026 lineup that matches four workload types to Claude Haiku 4.5, Sonnet 5, Opus 5, and Fable 5

Claude & Anthropic

Claude Haiku vs Sonnet vs Opus vs Fable: Models Compared

Start with Sonnet 5.5 in the Claude apps and Opus 5.5 in the API, move narrow high-volume work to Haiku 5.5, and try Fable 5.1 only when Opus falls short.

Oct 26, 202618 min

Claude Sonnet 5.5 vs Gemini 3.8 Flash: Flash is 2.67x cheaper per token but cost 2.42x as much over 11 identical test calls

Model Comparisons

Claude Sonnet 5.5 vs Gemini 3.8 Flash: Cost per Task, Tested

Gemini 3.8 Flash is 2.67x cheaper per token, yet on 11 identical calls at high effort on October 26, 2026 it cost 2.42x as much as Claude Sonnet 5.5.

Oct 26, 202618 min

Claude Sonnet 5.5 vs GPT-6 Luna: 20x per token, 5–8x per task at similar scores, 50x at API defaults

Model Comparisons

Claude Sonnet 5.5 vs GPT-6 Luna: 20x per Token, 5–50x per Task

Sonnet 5.5 costs 20x GPT-6 Luna per token and 5–50x per benchmark task. Luna fits volume and long documents; Sonnet fits agentic coding and scores above 38.

Oct 26, 202618 min