GitHub Copilot Reasoning Levels Guide — Low/Medium/High/x-High and AI Credits¶
For / Key Points
For: GitHub Copilot (Pro/Pro+/Enterprise) users who want to understand what the reasoning level selector actually controls
Key Points:
- Reasoning levels control how much the model "thinks" — same model, different thinking token budgets
- Under usage-based billing after June 2026, higher reasoning levels can consume more AI Credits
- Start with defaults, then raise effort for design decisions, multi-file work, and debugging
What Are Reasoning Levels?¶
VS Code 1.113 (March 25, 2026) introduced the Thinking Effort selector — a control that adjusts how deeply the model reasons before generating a response. Today, the model picker is the primary control surface, and the old github.copilot.chat.responsesApiReasoningEffort setting is deprecated.1
The model picker shows a submenu with levels such as Low / Medium / High when a selected model supports reasoning. Available levels vary by model and surface. Non-reasoning models do not show the Thinking Effort submenu.
The key point: changing the reasoning level does not change the model itself. The same GPT-5.4 at Low produces a minimal reasoning chain for an instant response, while at x-High it allocates significantly more thinking tokens for deeper analysis.
Supported Models and Levels¶
| Model family | Thinking Effort | Practical judgment |
|---|---|---|
| GPT-5.4 / GPT-5.3-Codex and similar reasoning models | Available when supported | Complex design and debugging |
| Claude Sonnet / Opus reasoning models | Available when supported | Quality-focused implementation and review |
| GPT-4.1 / GPT-4o / GPT-5 mini and similar models | Often not shown | Lightweight questions and routine chat |
| Claude Haiku / Gemini Flash and similar models | Often not shown | Speed- and cost-sensitive work |
Unsupported models (no reasoning level selector):
- GPT-4.1, GPT-4o, GPT-5 mini — non-reasoning models
- Claude Haiku 4.5, Gemini 3 Flash — speed-optimized
Do not freeze this as a static model table
GitHub Copilot models, extended context, and reasoning controls change quickly. Prefer the live model picker and official model documentation over static model names in this article.3
Cost: Reasoning Level Now Matters for AI Credits¶
This is the most important fact.
Under usage-based billing after June 2026, raising reasoning effort can increase AI Credits consumption.
GitHub explains Copilot cost as a function of the model and token consumption: input tokens, output tokens, and cached context are converted into AI Credits. GitHub's June 4, 2026 changelog also states that larger context windows or higher reasoning levels consume more AI Credits per interaction.23
In the legacy premium request model, it was sometimes reasonable to say "same model, same request multiplier." In the current AI Credits model, the same model can cost more if higher effort creates more thinking tokens or output.
| Cost lens | Legacy premium requests | AI Credits after June 2026 |
|---|---|---|
| Unit | Request count and model multiplier | Model price, input, output, cached context, thinking tokens |
| High effort | Often treated as the same multiplier for the same model | Can increase per-interaction consumption |
| Savings tactic | Reduce round trips | Reduce round trips, context size, and unnecessary effort |
So High is not a free quality switch. Use it when the task justifies deeper reasoning, but do not pin every lightweight chat to High or x-High.
What Each Level Actually Does¶
| Level | Behavior | Latency | Best For |
|---|---|---|---|
| Low | Minimal reasoning. Instant response | Fastest | Boilerplate, syntax questions |
| Medium / default | Balanced | Fast | General coding |
| High | Deep reasoning chain | Slightly slower | Refactoring, design decisions |
| x-High / extended thinking | Highest reasoning budget | Slowest and more likely to consume credits | Security audits, large migrations |
Watch Credit Consumption, Not Only Speed¶
Higher effort can improve results on complex work. The VS Code AI Credits optimization guide also warns that higher effort produces more thinking tokens, increasing both latency and credit consumption.4
Low is genuinely faster, but response quality drops noticeably on certain tasks. Multi-file refactoring at Low, for example, can miss cross-file dependencies.
When to Raise Effort¶
Raise effort based on quality risk.
| Situation | Recommendation |
|---|---|
| Naming, simple API questions, short explanations | Default or lightweight model |
| Small one- or two-file edits | Start with default, raise only if it fails |
| Multi-file refactoring | Consider High |
| Security review, migration design, incident analysis | Consider High or above |
| Long logs or repository-wide context | Narrow the scope first, then raise effort only if needed |
The key step is narrowing scope before raising effort. If you send a large context window and also raise effort, quality may improve, but AI Credits consumption is more likely to rise too.
Does Low Have a Place?¶
Yes, but it's limited.
Low works well for:
- Simple code completions and snippet generation
- "What's the signature for this function?" type questions
- Rapid feedback loops during prototyping
- Auto-generating doc comments
Avoid Low for:
- Multi-file refactoring
- Security review and vulnerability analysis
- DB schema changes or framework migrations
- Architecture decisions
The rule is simple: tasks that don't require thinking → Low or default. Tasks that need real reasoning → High or above.
But "when in doubt, use High" is no longer the right cost default. If you care about AI Credits, start with the default and raise effort only when the result is not good enough.
Recommended Configuration¶
Use task-based switching, not always-on High.
- Use defaults for routine chat, small edits, and explanation tasks.
- Use High for design decisions, multi-file edits, and root-cause analysis.
- Reserve x-High or extended thinking for security audits, large migrations, or failed prior attempts.
- Before combining long context with High effort, trim files, logs, and task scope.
Switch from the model picker
VS Code 1.113+ lets you switch Thinking Effort from the model picker for supported models. Prefer checking the UI per task instead of pinning the deprecated settings.json setting.
For broader cost design, read GitHub Copilot AI Credits Optimization.
Summary¶
- Reasoning levels control how much the model "thinks." The model itself doesn't change
- Under AI Credits, higher reasoning levels can consume more credits
- High is worth using for complex work where quality risk is high
- Start routine work at the default, then raise effort only when needed
Reasoning effort is a quality control. It is also a credit-consumption control. Treat it as a per-task decision, not a permanent maximum setting.
Related Articles¶
- GitHub Copilot AI Credits Optimization — Optimize usage-based billing and AI Credits consumption
- GitHub Copilot Hooks Complete Guide — Workflow automation
- GitHub Copilot Custom Instructions Guide — Improve prompt quality