PSA!! We built “DSA for LLMs”: a LeetCode-style benchmark for Context Engineering

If you're preparing for AI engineering interviews, you probably spend a lot of time on DSA, prompt engineering, RAG, and the usual stuff.

But when you actually work with LLMs in production, you run into a different problem pretty quickly: context gets messy and expensive.

You can have a 50k token context that still gives you a good answer, but you're also paying for a lot of unnecessary stuff. It can increase latency, increase token costs, and hurt the model's ability to focus on the information that actually matters.

That got us thinking about something.

In normal software engineering, you don't just care whether your code produces the correct output. A brute-force O(N²) solution might work perfectly, but it's still considered worse than a more efficient solution.

We think context should be treated the same way.

There wasn't really a good way to objectively measure the structural health of an LLM context before inference, so we built ContextOps, a deterministic structural analyzer, and then built ContextBench on top of it.

The easiest way to describe ContextBench is probably LeetCode for context engineering.

We created 1,500 pre-built context windows that act as the problem set.

You write an optimize_context() function that takes a broken context and returns an improved version.

The ContextOps engine then evaluates it using a 100% deterministic score based on structural efficiency, rather than semantic guessing.

The scoring is:

• Quality: 50%
• Compression: 35%
• Latency: 15%

You then get ranked on the ContextBench Leaderboard.

The 1,500 samples are split into five categories, with 300 problems in each:

1. Optimal Architectures: 300

These test whether you can avoid false positives on healthy pipelines.

2. Structural Failures: 300

Things like system prompt bloat and retrieval flooding.

3. Redundancy Failures: 300

Near-duplicate clusters and boilerplate explosion.

4. Agent Architecture Failures: 300

Multi-agent context explosion and tool chain bloat.

5. Temporal Context Drift: 300

Stale memory injection and invalidated historical state.

Every problem has a ground truth.

So if you flag redundancy where there isn't any, your score goes down. If you miss density bloat, your score also goes down.

The point isn't to blindly delete as many tokens as possible. You need to actually improve the context while preserving what's useful.

We also added a security track called ContextSecBench.

It's an adversarial CTF with 300 attack payloads covering things like:

• Truncation smuggling
• Prompt injection hiding
• Semantic Denial of Service (SDoS)

The idea is to test whether your optimizer can deal with malicious context as well, similar to testing an algorithm against adversarial inputs.

We think this is becoming relevant for AI engineering because just knowing how to put documents into a vector database isn't much of a differentiator anymore.

Understanding context architecture, redundancy, retrieval quality, token usage, agent context, and how all of that affects an LLM is becoming much more important.

So we wanted to make something where you can actually practice this and get an objective score instead of just saying you know context engineering.

If you're interested, give ContextBench a try, see how your optimizer performs, and try to get on the leaderboard. All of this is for free. There is no payment wall hidden anywhere. Star the repo so that you can comeback when preparing for interviews.

Would be interested to see what approaches people come up with.

Link : https://github.com/Abhijeet777ui/contextops