Claude AI Doesn't Get Worse — Scale Your Context

Why Claude AI Doesn't Get Worse: Scale Your Context for Success

There's a persistent myth among developers: AI assistants like Claude start strong and slowly degrade as a project grows. We tested that idea and found a different truth — Claude AI doesn't get worse. Projects get bigger, and if you don't scale the context you give the model, your collaboration will feel frustrating. This guide explains the data, a practical rule of thumb, and how tools like the Vibe-Log CLI tool can keep Claude Code working at its best.

The core misconception

When a Claude Code session stalls or produces poorer suggestions over time, many blame the model. The real issue is context. As codebases grow, the amount of relevant information Claude needs to make accurate decisions increases. If you keep using the same prompt length and don't surface new context, results will appear worse even though the model itself is unchanged.

What the data shows: scale context, not blame

In a controlled multi-week observation of vibe coding sessions, researchers tracked prompt length, number of messages, and successful feature completions across three weeks. Key takeaway: interaction counts and prompt content increased predictably as the project grew. Performance only dropped when context remained fixed while scope expanded.

• Observation: Claude performed reliably when given the full working directory context and up-to-date prompts.
• Quantified rule: Doubling or substantially increasing prompt context as project scope grows restored performance and reduced back-and-forth.
• Cost tradeoff: More context can increase processing fees (roughly $50 in some observed sessions), but saved developer time often outweighed these costs.

Why more context helps

Claude Code is agentic: it can read the working directory, make code changes, run tests, and iterate. But it needs the right signals to act effectively. Context helps by narrowing the model's search space, exposing dependencies and tests, and allowing validation against actual project structure instead of assumptions.

Meet the Vibe-Log CLI tool: track what matters

The Vibe-Log CLI tool was built to measure coding-session dynamics. It analyzes sessions and extracts productivity metrics, tracks prompt length and message counts, and provides emotional and productivity insights to help teams iterate on workflows.

• Analyzes coding sessions and extracts productivity metrics
• Tracks prompt length and message counts over time
• Provides emotional and productivity insights to help teams iterate on workflows
• Integrates with Claude Code and other AI coding assistants

Using Vibe-Log helps you spot when context size lags project complexity so you can proactively scale prompts instead of reacting to perceived model decline. Learn more at Vibe-Log and the project repo at GitHub.

Quick Vibe-Log example

npx vibe-log start --session my-feature
// Collects prompt length, messages, time-to-complete
npx vibe-log report --last 7d

Inside the vibe-log report you'll see trends like rising prompt lengths, more message exchanges per task, and where Claude required human intervention more often.

How to apply the "double context" rule in practice

Here is a simple, repeatable workflow to keep Claude Code productive as your project grows:

1. Baseline: Start each new feature with the current working directory and a focused prompt describing the goal, tests, and constraints.
2. Monitor: Use Vibe-Log CLI tool or manual checks to track message counts and failed attempts.
3. Scale: If the feature scope grows (more files, new modules, broader tests), increase the supplied context. Doubling relevant context is a practical heuristic: add more files, API schemas, recent PRs, and tests to the prompt.
4. Validate: Ask Claude to run tests and provide diffs. Let it iterate agentically until it asks for human input or tests pass.
5. Optimize: Remove noise. Only add context that matters to the task (avoid feeding entire unrelated directories).

That's the difference between thinking the model is worse and giving Claude the information it needs to stay effective.

What "scaling context" looks like

• Add related files and modules, not everything in the repo.
• Include recent failing tests and their stack traces.
• Attach API contracts, database migrations, or sample env variables if they affect behavior.
• Include short changelogs or relevant PR comments to show intent.

Cost vs. benefit: why spending more tokens can be worth it

Feeding more context increases processing fees and token usage. Consider the alternatives: manual debugging, time spent explaining code state across multiple messages, and repeated fixes. In many observed projects, doubling context reduced total interaction rounds and the number of manual interventions, saving net developer time.

Practical tips to control cost:

• Prioritize high-value context for each task.
• Use the Vibe-Log CLI to measure the marginal benefit of added context.
• When iterating, prefer incremental context increases rather than huge single jumps.

Practical setup: Claude Code + Vibe coding workflow

Claude Code typically runs in a single directory workspace and integrates with terminal workflows. It's not a full IDE replacement, but it shines as an agentic assistant when you provide the right context.

Suggested workflow:

1. Open your feature branch directory in the terminal.
2. Start a Vibe-Log session to capture metrics.
3. Provide Claude a focused prompt that includes files, tests, and a short objective.
4. Let Claude make edits, run tests, and iterate. Approve or modify changes as needed.
5. If the project grows or you hit blockers, increase context (add files, tests, API contract) and continue.

Case studies: short examples

1) Small feature, small context

A one-file bugfix: a focused prompt with the file and failing test yielded a single Claude iteration and green tests.

2) Feature growth mid-iteration

Working on a feature that added new DB migrations and API hooks: initial prompts were insufficient. After doubling context to include the migration, schema, and relevant tests, Claude finished the feature with fewer iterations.

3) Cross-cutting refactor

For large refactors, provide high-level architecture notes, affected modules, and test suites. Use Vibe-Log to track whether more context reduced rework.

Common questions (FAQ)

Q: Is Claude actually getting worse over time?

A: No. The model isn't degrading; projects are. As scope grows, Claude needs proportionally more context. Treat the fix as an information problem, not a reliability problem.

Q: How much context is too much?

A: Too much is noisy and costly. Focus on relevance: files and tests that affect the task. Use Vibe-Log metrics to find diminishing returns.

Q: Will adding context always increase costs linearly?

A: Token usage increases, but the total number of iterations and developer time usually drops. Measure both token cost and developer hours to make the best tradeoff.

Q: Can Claude make unsafe changes if I give too much access?

A: Claude is agentic but you control approvals in most workflows. Use code reviews, CI tests, and staged deployments as guardrails.

Best practices checklist

• Start with a focused prompt and the minimum required files.
• Monitor message counts and failure rates with Vibe-Log CLI tool.
• When scope grows, scale context — doubling relevant context is a good heuristic.
• Prioritize relevant tests, API contracts, and migration files in prompts.
• Keep human review and CI gates in place for safety.

Conclusion: scale context, not blame

Claude AI doesn't get worse; projects get bigger. The solution is clear: proactively scale the context you provide. Use the Vibe-Log CLI tool to measure when context is lagging and apply the doubling heuristic to restore efficiency. With a data-backed workflow, Claude Code becomes a predictable, reliable partner rather than a mysterious, declining collaborator.

Want to try this today? Start a Vibe-Log session, measure prompt length trends, and the next time a feature grows mid-flight, increase the context and watch the interaction rounds drop.

References: Vibe-Log, GitHub repo, Article: Vibe Coding with Claude Code.