Extended Reasoning Mode With Explicit Chain Of Thought

via “chain-of-thought-multi-stage-reasoning”

Google's vision-language-action model for robotics.

Unique: Integrates chain-of-thought reasoning directly into the action generation pipeline by representing both reasoning steps and actions as text tokens, allowing the same transformer to generate interpretable intermediate steps and grounded robot actions

vs others: Provides interpretability and reasoning transparency that black-box policy networks lack, while avoiding separate symbolic reasoning systems by leveraging the language model's native ability to generate and process reasoning text

via “extended reasoning with iterative refinement”

Opus 4.5 is not the normal AI agent experience that I have had thus far

Unique: Opus 4.5 exposes reasoning artifacts as first-class outputs that developers can inspect and interact with, rather than keeping reasoning internal — this enables debugging, validation, and guided refinement of agent decision-making in ways previous models obscured

vs others: Differs from standard LLM agents by making reasoning transparent and inspectable rather than treating it as a black box, enabling developers to understand failure modes and guide the model toward better solutions

via “multi-step reasoning with internal thought chains”

Proactive personal AI agent with no limits

Unique: Maintains explicit reasoning state across steps with backtracking capability, allowing the agent to revise earlier conclusions rather than committing to single-pass inference like most LLM-based agents

vs others: Provides better explainability than black-box agents by exposing intermediate reasoning, though at the cost of increased latency compared to single-pass inference approaches

via “extended reasoning with native thinking mode”

Gemini 2.5 Flash is Google's state-of-the-art workhorse model, specifically designed for advanced reasoning, coding, mathematics, and scientific tasks. It includes built-in "thinking" capabilities, enabling it to provide responses with greater...

Unique: Integrates reasoning as a first-class inference primitive rather than a prompt engineering technique, using an internal thinking phase that explores solution spaces before output generation, with separate token accounting for transparency

vs others: Provides more reliable reasoning than prompt-based CoT approaches (like o1-preview) while maintaining faster inference than full-chain reasoning models, with explicit visibility into thinking token usage

via “chain-of-thought reasoning with explicit step decomposition”

Claude Opus 4.1 is an updated version of Anthropic’s flagship model, offering improved performance in coding, reasoning, and agentic tasks. It achieves 74.5% on SWE-bench Verified and shows notable gains...

Unique: Constitutional AI training enables natural reasoning articulation without explicit chain-of-thought prompting, producing coherent reasoning traces that reflect actual model decision-making rather than post-hoc rationalization

vs others: Reasoning quality and naturalness exceed GPT-4's chain-of-thought due to instruction tuning specifically for reasoning transparency, producing more interpretable intermediate steps

via “complex reasoning and chain-of-thought decomposition”

Command R7B (12-2024) is a small, fast update of the Command R+ model, delivered in December 2024. It excels at RAG, tool use, agents, and similar tasks requiring complex reasoning...

Unique: Command R7B's reasoning is optimized for RAG and tool-use contexts, where intermediate steps can reference retrieved documents or tool outputs, enabling grounded reasoning that combines external knowledge with logical inference

vs others: Outperforms GPT-4 on MATH and AIME benchmarks when combined with tool use for calculation, because it can delegate computation to tools rather than attempting symbolic math in-context

via “extended reasoning with implicit chain-of-thought”

Grok 4 is xAI's latest reasoning model with a 256k context window. It supports parallel tool calling, structured outputs, and both image and text inputs. Note that reasoning is not...

Unique: Implicit reasoning allocation based on problem complexity, with reasoning traces integrated into output without explicit token budget management, contrasting with OpenAI's explicit reasoning token approach

vs others: More transparent reasoning than GPT-4o (which hides reasoning) but less controllable than o1 (which offers explicit reasoning token budgets); better for exploratory reasoning where depth is problem-dependent

via “extended-chain-of-thought-generation”

Hermes 4 70B is a hybrid reasoning model from Nous Research, built on Meta-Llama-3.1-70B. It introduces the same hybrid mode as the larger 405B release, allowing the model to either...

Unique: Combines 70B parameter scale with process-reward modeling to maintain reasoning coherence across 10+ step chains, whereas smaller models typically degrade after 3-4 steps due to context drift and accumulated errors

vs others: Produces more reliable multi-step reasoning than GPT-3.5 while being more cost-effective than GPT-4 for reasoning tasks, with explicit step visibility that proprietary models don't expose

via “chain-of-thought reasoning with explicit step-by-step generation”

Claude Sonnet 4.5 is Anthropic’s most advanced Sonnet model to date, optimized for real-world agents and coding workflows. It delivers state-of-the-art performance on coding benchmarks such as SWE-bench Verified, with...

Unique: Extended thinking mode allows explicit reasoning generation with token-level control, vs alternatives that only support prompt-based chain-of-thought, enabling more reliable and measurable reasoning improvements

vs others: More transparent reasoning than GPT-4 on complex tasks due to explicit thinking token generation, and faster than o1 while maintaining reasonable accuracy on most reasoning tasks

via “structured reasoning with chain-of-thought explanation generation”

Hermes 3 is a generalist language model with many improvements over Hermes 2, including advanced agentic capabilities, much better roleplaying, reasoning, multi-turn conversation, long context coherence, and improvements across the...

Unique: Hermes 3 405B's reasoning improvements come from instruction-tuning on reasoning-focused datasets (similar to techniques used in models like Llama 2 with chain-of-thought training). The 405B parameter scale enables more complex reasoning chains with better logical consistency.

vs others: Provides more transparent reasoning than smaller models like Mistral 7B, though may not match GPT-4's reasoning depth on highly complex mathematical or logical problems.

via “extended-reasoning-chain-of-thought-generation”

ERNIE-4.5-21B-A3B-Thinking is Baidu's upgraded lightweight MoE model, refined to boost reasoning depth and quality for top-tier performance in logical puzzles, math, science, coding, text generation, and expert-level academic benchmarks.

Unique: Uses proprietary A3B (Adaptive Attention-Based Branching) mechanism that dynamically allocates compute across reasoning paths rather than fixed-depth chains, enabling adaptive reasoning depth based on problem complexity. This differs from static chain-of-thought approaches by treating reasoning as a branching tree with learned pruning heuristics.

vs others: Outperforms GPT-4 and Claude on mathematical reasoning benchmarks while maintaining 21B parameter efficiency through MoE architecture, making it faster and cheaper for reasoning-heavy workloads than larger closed-source models

via “chain-of-thought reasoning with explicit step decomposition”

GPT-4.1 is a flagship large language model optimized for advanced instruction following, real-world software engineering, and long-context reasoning. It supports a 1 million token context window and outperforms GPT-4o and...

Unique: Implements chain-of-thought as a first-class reasoning pattern with architectural support for maintaining reasoning coherence across long inference chains, enabling transparent multi-step problem solving

vs others: Produces more reliable reasoning than GPT-4o on complex problems because it maintains reasoning context better across longer chains and has been optimized specifically for instruction following in reasoning tasks

via “reasoning chain decomposition and step-by-step problem solving”

Qwen Plus 0728, based on the Qwen3 foundation model, is a 1 million context hybrid reasoning model with a balanced performance, speed, and cost combination.

Unique: Implements chain-of-thought reasoning through prompt-based guidance rather than architectural modifications, enabling flexible reasoning depth control without model retraining

vs others: More cost-effective than specialized reasoning models (o1) for moderate complexity problems; produces transparent reasoning vs black-box outputs; trades off reasoning depth vs cost and latency

via “long-context reasoning with extended thinking”

Claude Opus 4.5 is Anthropic’s frontier reasoning model optimized for complex software engineering, agentic workflows, and long-horizon computer use. It offers strong multimodal capabilities, competitive performance across real-world coding and...

Unique: Implements internal chain-of-thought reasoning within a 200K token window using transformer attention mechanisms, allowing reasoning to occur before output generation without requiring explicit prompt engineering for step-by-step thinking

vs others: Outperforms GPT-4o and Claude 3.5 Sonnet on complex reasoning tasks by maintaining coherence across longer reasoning chains while keeping the 200K context window practical for real-world applications

via “hybrid-reasoning-with-explicit-thinking-mode”

DeepSeek-V3.1 is a large hybrid reasoning model (671B parameters, 37B active) that supports both thinking and non-thinking modes via prompt templates. It extends the DeepSeek-V3 base with a two-phase long-context...

Unique: Implements user-controlled explicit thinking via prompt templates rather than always-on reasoning, allowing per-request cost-performance optimization. The 37B active parameter subset processes thinking tokens in a separate phase before final generation, unlike models that interleave reasoning throughout decoding.

vs others: Offers finer-grained reasoning control than OpenAI o1 (which always reasons) and better cost efficiency than Claude 3.5 Sonnet's extended thinking by letting developers opt-in only when needed.

via “reasoning-aware response generation with chain-of-thought transparency”

GLM-4.5 is our latest flagship foundation model, purpose-built for agent-based applications. It leverages a Mixture-of-Experts (MoE) architecture and supports a context length of up to 128k tokens. GLM-4.5 delivers significantly...

Unique: Chain-of-thought reasoning is trained directly into the model rather than implemented as a decoding strategy; the model learns to generate reasoning steps as part of its core training objective

vs others: More natural and coherent reasoning steps than prompt-injection approaches (e.g., appending 'think step by step') because reasoning is learned as a first-class capability

via “reasoning and chain-of-thought decomposition”

Mistral Large 2 2411 is an update of [Mistral Large 2](/mistralai/mistral-large) released together with [Pixtral Large 2411](/mistralai/pixtral-large-2411) It provides a significant upgrade on the previous [Mistral Large 24.07](/mistralai/mistral-large-2407), with notable...

Unique: Mistral Large 2411 implements implicit chain-of-thought through training on reasoning-heavy datasets, enabling natural step-by-step decomposition without explicit prompting while maintaining efficiency through optimized token generation

vs others: Provides reasoning quality comparable to GPT-4 while maintaining lower latency and cost through more efficient token usage

via “reasoning-focused problem decomposition and chain-of-thought”

This is Mistral AI's flagship model, Mistral Large 2 (version mistral-large-2407). It's a proprietary weights-available model and excels at reasoning, code, JSON, chat, and more. Read the launch announcement [here](https://mistral.ai/news/mistral-large-2407/)....

Unique: Trained specifically on chain-of-thought datasets to prioritize reasoning steps, using attention mechanisms that weight intermediate reasoning tokens higher than direct answers, enabling more transparent problem-solving

vs others: Comparable to GPT-4's reasoning on complex problems, while maintaining lower latency and cost; outperforms Llama 2 on multi-step reasoning due to larger parameter count and specialized training

via “extended reasoning with chain-of-thought for complex visual tasks”

Qwen3-VL-30B-A3B-Thinking is a multimodal model that unifies strong text generation with visual understanding for images and videos. Its Thinking variant enhances reasoning in STEM, math, and complex tasks. It excels...

Unique: Integrates extended reasoning directly into the model's forward pass for visual tasks, rather than using post-hoc prompting techniques like 'think step-by-step', enabling the model to allocate compute dynamically to reasoning-heavy visual problems

vs others: More reliable than prompt-based chain-of-thought for visual reasoning because reasoning is baked into model weights, not dependent on prompt engineering; produces more consistent intermediate steps for STEM tasks

via “reasoning-and-planning-with-extended-chain-of-thought”

Compared with GLM-4.5, this generation brings several key improvements: Longer context window: The context window has been expanded from 128K to 200K tokens, enabling the model to handle more complex...

Unique: Extended context window enables multi-page chain-of-thought reasoning without truncation, allowing the model to explore multiple reasoning paths, backtrack, and reconsider assumptions within a single generation rather than requiring multiple API calls

vs others: Produces more transparent and verifiable reasoning than models with shorter context windows because it can maintain full reasoning history; enables human-in-the-loop validation of intermediate steps rather than just final answers