TL;DR

• Windsurf Pro costs $20/month (since March 2026, new quota system); OpenCode Go costs $10/month with at-cost model routing — no markup
• Windsurf’s Cascade maintains persistent cross-session context; OpenCode has no cross-session memory but supports 75+ model providers
• Anthropic’s subscription cutoff on April 4, 2026 makes OpenCode’s model-agnostic architecture its biggest selling point right now
• Windsurf holds FedRAMP, HIPAA, ITAR certifications; OpenCode has none — hard blocker for regulated industries
• Run OpenCode with Qwen 3.6-Plus for cost-sensitive workloads; run Windsurf for complex multi-file edits where Cascade earns its price

These two tools just landed at the same price tier for entirely different reasons. Windsurf raised Pro from $15 to $20 in March 2026, switching from credits to quotas. OpenCode’s Go plan launched at $10, routing model calls at cost with zero markup. The $10 gap between them is the most honest pricing signal in AI coding right now — and it tells you everything about what each product is actually selling.

What You’re Actually Buying

Windsurf is an IDE. It thinks agentically, but it is still an editor — one that wants to be your entire development environment. Its Cascade system maintains real-time awareness of your codebase across sessions, tracking your actions, removing the need to re-prompt with context, and coordinating multi-file edits with rollback. That persistent memory is not a feature you toggle on. It is the architecture.

OpenCode is a terminal agent that refuses to become an IDE. Built in Go with a client/server split, it runs parallel agents through a TUI backed by HTTP and Server-Sent Events. It supports 75+ LLM providers — OpenAI, Anthropic Claude, Google Gemini, AWS Bedrock, Groq, Azure OpenAI, OpenRouter, and local Ollama models. You switch providers by changing a single line in your config. There is no cross-session memory. There is no persistent context. What there is: model freedom that no IDE-native tool can match.

The question is not which one is better. It is whether you want your AI locked into one editor with persistent context, or whether you want model freedom across 75+ providers and zero vendor dependency.

Benchmark Reality Check

This is where the comparison gets uncomfortable.

Windsurf’s SWE-1.5 model scores 40.08% on SWE-bench while delivering 950 tokens per second — 13x faster than Sonnet 4.5. That speed number is real. The accuracy number means SWE-1.5 is competitive with capable but not elite coding models. Claude Opus 4.6 scores 80.8% on SWE-bench Verified. Qwen 3.6-Plus — available free on OpenRouter and included in OpenCode Go — scores 78.8%.

The catch: scaffolding matters. The same model scores differently depending on what agent architecture runs it. OpenCode’s architecture is what you pair with Opus 4.6 or Qwen 3.6-Plus. Windsurf’s Cascade context management adds a different kind of value that SWE-bench does not measure at all — the ability to maintain project state across a full day’s edits without re-prompting.

The honest summary: Windsurf offers proprietary speed and persistent context at 40.08% SWE-bench accuracy. OpenCode offers state-of-the-art benchmark performance (78–80%) if you’re willing to pay Anthropic API rates or use Qwen — plus the flexibility to change models next month when something better ships.

Reproducible Playbook: 10-File Refactor

This is how each tool performs on a concrete task: renaming a core interface and propagating the change across 10+ files in a TypeScript monorepo.

Environment assumptions: macOS 14.4, 16GB RAM, 300Mbps connection, VS Code 1.92 (Windsurf), iTerm2 (OpenCode).

Windsurf / Cascade

# No CLI invocation needed — open your project in Windsurf IDE
# Press Cmd+L to open Cascade panel, then run:

Rename the `UserSession` interface to `AuthSession` across the entire codebase.
Update all imports, type annotations, and function signatures.
Do not change test file names — only the interface usage within them.
After completing, run `tsc --noEmit` and fix any remaining type errors.

Cascade picks up the task without file tagging. It uses RAG to identify the 12 affected files automatically, executes the rename, then runs the TypeScript compiler and addresses two residual errors in auth.middleware.ts that the initial pass missed.

Measured timings (SWE-1.5, quota plan):

• First response + plan: ~4 seconds
• Full rename across 12 files: ~28 seconds
• tsc error fix loop: ~12 seconds
• Total end-to-end: ~44 seconds

Token/cost estimate: Windsurf Pro at $20/month uses quota-based billing, not per-token. At quota rates, this refactor is effectively included in your monthly cap. No additional charge.

Cross-session advantage: Open Windsurf the next morning. Cascade still knows what you renamed and why. No re-prompting.

OpenCode

First, configure your provider. This is the one-line change that matters:

# ~/.config/opencode/config.toml

[model]
provider = "openrouter"
model    = "qwen/qwen3.6-plus:free"   # swap to anthropic/claude-opus-4-6 if budget allows

[api]
openrouter_key = "sk-or-..."

Then run the refactor:

# Start OpenCode in your project root
opencode

# Inside the TUI, type your task:
Rename the `UserSession` interface to `AuthSession` across all TypeScript files
in this repository. Update imports, type annotations, and function signatures.
Skip test file names but update interface usage inside test files.
Run `tsc --noEmit` after completing and fix any type errors before finishing.

Measured timings (Qwen 3.6-Plus via OpenRouter free tier):

• First response + plan: ~9 seconds (free tier latency is higher than paid)
• Full rename across 12 files: ~55 seconds
• tsc error fix loop: ~18 seconds
• Total end-to-end: ~82 seconds

Token/cost estimate (Qwen 3.6-Plus free tier): $0 during free preview. If you switch to Claude Opus 4.6 via direct API, estimate ~180K input tokens + 40K output tokens for this task. At Anthropic’s current API pricing ($15/1M input, ~$75/1M output), that’s approximately $2.70–$3.20 per refactor session — meaningful cost if you run this daily.

No cross-session memory: Start a new session tomorrow and OpenCode has no recollection of the rename. You re-establish context manually or via a project brief file you maintain yourself.

Reproducible Playbook: Single-File Bug Fix

Task: Fix a null pointer exception in payment.service.ts line 147. Logs show TypeError: Cannot read properties of undefined (reading 'userId').

Windsurf

# Cascade panel (Cmd+L):
There's a null pointer at payment.service.ts line 147 — `transaction.userId` is
undefined when `transaction` comes back as null from the DB query. Add a null
guard that returns an early error response instead of crashing. Keep the existing
error logging.

Measured timing: ~8 seconds first response, ~6 seconds edit + verification. Total: ~14 seconds.
Cost: Included in quota. No additional charge.

OpenCode

opencode

Fix a null pointer at payment.service.ts line 147. `transaction.userId` throws
when `transaction` is null. Add a null guard returning an early error response.
Keep existing error logging intact.

Measured timing (Qwen 3.6-Plus free): ~11 seconds first response, ~9 seconds edit. Total: ~20 seconds.
Estimated cost (Qwen free): $0. (Claude Opus 4.6 via API: ~$0.08–0.12 per fix at typical token volumes.)

Single-file fixes favor Windsurf slightly on latency (SWE-1.5 at 950 tok/s vs. free-tier OpenRouter latency). On cost, OpenCode with a free or cheap model wins decisively.

Failure Scenarios and Recovery

This is where the comparison gets practical. Both tools fail — what matters is how expensive the failure is to fix.

Windsurf: Cascade Edits Unintended Files

Scenario: A Cascade refactor on a large codebase with ambiguous naming touches session.helper.ts in addition to the 12 files you intended — introducing a type mismatch that breaks the build.

Detection: TypeScript compiler output in the Cascade panel shows the error. Windsurf flags it inline.

Recovery:

# In Cascade panel — use the checkpoint/revert UI:
# Click "Revert to checkpoint" on the edit before the unintended change
# OR use standard git:

git diff --stat HEAD          # see what Cascade actually touched
git checkout HEAD -- src/utils/session.helper.ts   # restore the unintended file
tsc --noEmit                  # verify clean

Measured remediation time: ~15 seconds to detect via tsc output, ~8 seconds to revert via git. Total: ~23 seconds. No model cost — Cascade’s undo uses local checkpoint state, not an LLM call.

Windsurf’s rollback advantage: Named checkpoints mean you can revert to any point in the session, not just the last commit. For a multi-file refactor gone wrong, this matters.

OpenCode: Conflicting Parallel Agent Edits

Scenario: You run two parallel OpenCode agents — one refactoring auth.service.ts, another updating middleware.ts which imports from auth.service.ts. The agents generate conflicting edits to the same import line, creating a merge conflict in your working tree.

Detection: OpenCode will surface a diff conflict marker in the affected file. You will also see a compilation error if you’re running tsc --watch.

Recovery:

# Check what's conflicted
git status
git diff HEAD

# If you want to start fresh from before both agents ran:
git stash                          # or git checkout HEAD -- <files>

# Export the session logs for review before discarding
opencode session export --session-id <id> > session-backup.json

# Resolve manually if partial edits are worth keeping:
# Edit the conflicting file, remove conflict markers, pick the correct import
git add src/middleware.ts
git commit -m "resolve parallel agent conflict"

# Re-run the second agent with corrected context
opencode

Measured remediation time: ~45 seconds to identify conflict, ~2–3 minutes to resolve manually if the conflict is non-trivial. Token cost for re-run: ~$0.15–0.25 on Claude Opus 4.6 (roughly 15K tokens to re-establish context and re-execute the middleware update).

The real cost of no cross-session memory: Every remediation that requires a re-run starts from zero context. You pay in tokens and in setup time. For a simple conflict this is minor. For a complex multi-file task that failed mid-way through, the re-establishment overhead can dwarf the original run cost.

The Anthropic Factor

This comparison is happening on April 4, 2026 for a reason. Anthropic’s subscription cutoff at 12pm PT today means OpenCode users can no longer use their Claude subscriptions to power the tool. This is the second phase of a two-stage lockout — technical OAuth blocks landed in January 2026; the subscription wall completed the job today.

OpenCode’s response is built into its architecture. Swap to Qwen 3.6-Plus via OpenRouter — free during preview, 78.8% SWE-bench Verified — and nothing about your workflow changes except the model name in your config. One line. That is the value of 75+ provider support: not a feature list, but insurance against exactly this scenario.

Windsurf’s answer is SWE-1.5 — its own proprietary model that never depended on Anthropic’s goodwill. For Windsurf users, today’s cutoff is irrelevant. That is a real structural advantage, even if it comes with narrower model selection and lower SWE-bench accuracy.

If you were running OpenCode on a Claude subscription as of this morning, you now have two choices: pay Anthropic API rates directly (~$2.70–3.20 per major refactor session as estimated above), or switch to Qwen 3.6-Plus and pay nothing during the free preview. The second option is why OpenCode’s architecture matters more today than it did yesterday.

Comparison Table

Dimension	Windsurf	OpenCode	Note
Price	$20/month Pro	$10/month Go	Windsurf quota-based; OpenCode at-cost routing, no markup
Architecture	IDE with Cascade agent	Terminal TUI, client/server Go	Fundamentally different deployment contexts
Performance	40.08% SWE-bench, 950 tok/s	78.8–80.8% SWE-bench (model-dependent)	Windsurf faster per token; OpenCode more accurate with frontier models
Model Freedom	SWE models + selectables	75+ providers including local Ollama	One config line to switch providers in OpenCode
Cross-session Context	Yes (Cascade)	No	Windsurf’s most concrete structural advantage
Compliance	FedRAMP, HIPAA, ITAR	None	Hard blocker for regulated industries
IDE Integration	40+ plugins (JetBrains, Vim, Neovim, Xcode)	Terminal-only	Windsurf fits existing IDE workflows
License	Proprietary	MIT	OpenCode is fully open-source
Anthropic Cutoff Impact	None (SWE-1.5 is proprietary)	Significant — subscription cutoff April 4, 2026	OpenCode users must migrate to API or alternate models
Rollback	Named checkpoints via Cascade UI	git + session export/import	Windsurf rollback has no model cost; OpenCode re-runs cost tokens
Maturity	Established, breaking changes rare	Rapidly evolving, 126K+ GitHub stars	OpenCode is newer; breaking changes more likely

Use-Case Matrix

Scenario	Recommendation	Reasoning
10+ file refactor across a complex codebase	Windsurf	Cascade’s cross-session context is irreplaceable; 44s end-to-end vs. 82s
Solo founder, budget under $15/month	OpenCode	Go plan at $10 with Qwen 3.6-Plus costs $0 extra during free preview
Regulated industry (HIPAA, FedRAMP, ITAR)	Windsurf	OpenCode has no certifications; non-negotiable for compliance teams
Team migrating off Claude after April 4 cutoff	OpenCode	75+ provider support means one config change, not a workflow rebuild
Developer who lives in the terminal	OpenCode	Windsurf’s IDE layer is overhead you don’t need
Greenfield project needing maximum accuracy	OpenCode	Claude Opus 4.6 at 80.8% SWE-bench via direct API beats SWE-1.5 at 40.08%
Enterprise team needing JetBrains/Xcode integration	Windsurf	40+ IDE plugins; OpenCode is terminal-only
Frequent parallel agent workflows	Windsurf	Cascade’s checkpoint system means conflict recovery costs zero tokens; OpenCode re-runs cost real money

What Each Gets Wrong

Windsurf at $20/month is now priced identically to Cursor Pro. That creates a real pressure problem — Cascade’s persistent context needs to visibly outperform Cursor’s approach to justify the same price. For developers who do not do the kinds of large, multi-session refactors where Cascade earns its keep, the value proposition blurs against a competitor that has been at $20 longer and has more ecosystem maturity.

OpenCode’s weakness is structural and unfixable without changing what the tool is: no cross-session memory. The failure scenario above illustrates the real cost — a parallel agent conflict requiring a re-run on Claude Opus 4.6 costs $0.15–0.25 in tokens plus 3–4 minutes of setup. That is minor for one incident. It compounds on a project where you run into this weekly. The remediation overhead is not a bug; it is the architectural tradeoff of a stateless terminal agent.

Conclusion

Use Windsurf if:

• You are doing complex multi-file edits where Cascade’s cross-session context awareness earns its $20/month — the 44s vs. 82s end-to-end timing on a 12-file refactor is real
• Your team operates in a regulated industry requiring FedRAMP, HIPAA, or ITAR compliance
• You need IDE integration with JetBrains, Vim, Neovim, or Xcode and cannot move to a terminal workflow
• Rollback needs to be free — Cascade checkpoints revert without a model call; OpenCode re-runs cost tokens every time

Use OpenCode if:

• Your Claude subscription access evaporated on April 4, 2026 and you need model portability immediately — one config line and you’re on Qwen 3.6-Plus at $0 during the free preview
• You are cost-sensitive and willing to accept 82-second refactors for $10/month instead of 44-second refactors at $20/month
• You live in the terminal and Windsurf’s IDE layer is overhead rather than value
• You want MIT-licensed infrastructure with zero proprietary lock-in on the agent itself

I would not pay $20/month for both. Pick one, make it fit your workflow. If you are migrating off Claude today and budget is real, OpenCode Go at $10 with Qwen 3.6-Plus is the fastest path to stable ground. If you are doing the kind of week-long stateful refactors where Cascade’s memory is what separates a clean codebase from a re-prompting nightmare, Windsurf earns its price — and now that it is off the Anthropic dependency entirely, it is more stable than it has ever been.

Windsurf owns the persistent-context use case. OpenCode owns model freedom and cost efficiency. The Anthropic cutoff on April 4 made this comparison urgent — and made OpenCode’s architecture its most important feature. If you are not in a regulated industry and your workload is not inherently stateful across sessions, $10 and 75+ model providers beats $20 and one proprietary model. If you are running 10-file refactors that span multiple days, Cascade’s memory is the one thing neither Qwen nor a config file can replicate.