Home › Tracks › Agentic Systems & Harness Engineering › Planning, Adaptive Reasoning Scaling & Test-Time Compute
Week 4 concept
Planning, Adaptive Reasoning Scaling & Test-Time Compute
Engineer harnesses for always-on adaptive reasoning models where internal reasoning tokens cannot be toggled off. Scale test-time compute via search, dynamic thinking token allocation, refusal category handling, and outer-loop verification.
Bridges to Artificial Intelligence — search, planning, and state-space reasoningBuilds on: Dynamic Inline Tooling, MCP & Cache-Preserving Toolmaking
Study notes
Master this concept.
Planning, Adaptive Reasoning Scaling & Test-Time Compute
What it is
This concept focuses on managing "reasoning models", AI systems that generate internal chains of thought before providing a final answer. Unlike standard models, these systems use "test-time compute," meaning they spend more processing power during the inference phase to think through complex problems. Adaptive reasoning scaling is the process of dynamically adjusting how much "thinking" the model does based on the difficulty of the task.
Why it matters
In production agentic systems, not every task requires deep reasoning. Using maximum compute for a simple greeting is wasteful, but using minimum compute for a complex architectural bug leads to failure. Because internal reasoning tokens often cannot be toggled off manually, engineers must build "harnesses", external control structures, that manage how the model allocates its mental effort and verifies its own logic.
Core concepts to master
- Test-Time Compute: The principle that increasing the amount of computation during the response phase (via search or extended reasoning) can improve accuracy more than simply increasing the model size.
- Dynamic Token Allocation: Strategies for determining when a model should "think longer" versus when it should provide a concise answer.
- Search & Verification: Implementing outer-loop checks (like self-correction or multi-path sampling) to verify if the model's internal reasoning actually led to a correct conclusion.
- Refusal Handling: Managing how the model handles "impossible" tasks to prevent it from wasting compute on infinite reasoning loops without reaching a solution.
Common mistakes
- Over-reliance on internal logic: Assuming the model's internal reasoning is always correct; without an outer-loop verification harness, the model can "hallucinate" a logical path to a wrong answer.
- Compute inefficiency: Failing to implement a trigger system that scales compute up or down, leading to high latency for simple queries.
- Ignoring refusal categories: Not defining clear boundaries for when the model should stop reasoning and simply refuse the task.
Connection to the track
This serves as the "brain" management layer for Agentic Systems. While other parts of the track focus on tool use and environment interaction, this concept ensures the agent has the cognitive depth required to plan those interactions and the verification layers to ensure they are executed accurately.
Go to the source
Read, watch, and practice.
Free, world-class material chosen for this concept.
- Paper Scaling LLM Test-Time Compute Optimally Can Be More Effective than Scaling Model Parameters arXiv (Snell et al.) Free (opens in a new tab)
- Paper ReAct: Synergizing Reasoning and Acting in Language Models arXiv (Yao et al.) Free (opens in a new tab)
- Guide Building Effective Agents Anthropic Free (opens in a new tab)
- Course Stanford CS25: Transformers United — agent and reasoning lectures Stanford University Free (opens in a new tab)