Zero Context Window Cost: How MemoClaw Keeps Your OpenClaw Agent Fast and Cheap
Hereβs a number that might bother you: if your MEMORY.md is 3,000 tokens and you use Claude Sonnet, youβre spending roughly $0.009 per message just on memory. Thatβs before the actual conversation. Before your agent reads any files. Before it thinks about your question. Just the memory tax.
Multiply that by 50 messages a day and youβre at $0.45/day on context you mostly donβt need. Over a month, thatβs ~$13.50 on tokens your agent skimmed past to find the one line that mattered.
MemoClaw costs $0.005 per recall. One recall per message, only when the agent actually needs context. For most conversations, thatβs fewer than 10 recalls a day. $0.05/day. Probably less.
Let me break down why.
The MEMORY.md problem
Every OpenClaw agent starts the same way. The AGENTS.md file says βread MEMORY.mdβ and the agent dumps the whole file into context. Every session. Every message. The entire file.
This made sense when MEMORY.md was 20 lines. But files grow. After a month of daily use, a typical MEMORY.md hits 2,000-4,000 tokens. Iβve seen some over 10,000.
The math is simple. Every token in your context window costs money, and MEMORY.md tokens are the worst kind: theyβre always there, most of them arenβt relevant to the current message, and they push out space that could be used for actual work.
Hereβs what a typical session looks like token-wise:
System prompt: ~500 tokens
AGENTS.md: ~800 tokens
MEMORY.md: ~3,000 tokens β this is the problem
USER.md: ~200 tokens
Conversation: ~2,000 tokens
---
Total: ~6,500 tokens
MEMORY.md is 46% of your input context. Almost half your tokens are memory, and on any given message, maybe 5% of those memories are relevant.
What MemoClaw does differently
Instead of loading everything, MemoClaw stores memories as individual records with vector embeddings. When your agent needs context, it makes a recall call with a relevant query and gets back just the matching memories.
A recall for βwhat language does the user preferβ might return 3 memories totaling 150 tokens. Not 3,000. Just the ones that match.
memoclaw recall "user's preferred programming language" --limit 3
Returns something like:
ββββββ¬ββββββββββββββββββββββββββββββββββββββ¬βββββββββββββ¬ββββββββββ
β ID β Content β Importance β Score β
ββββββΌββββββββββββββββββββββββββββββββββββββΌβββββββββββββΌββββββββββ€
β 42 β User prefers TypeScript over JS β 0.8 β 0.94 β
β 15 β Always use .ts extensions, not .js β 0.7 β 0.89 β
β 73 β User's main project is in TypeScriptβ 0.5 β 0.82 β
ββββββ΄ββββββββββββββββββββββββββββββββββββββ΄βββββββββββββ΄ββββββββββ
Three memories. ~80 tokens. Exactly what the agent needed.
The cost comparison
Letβs do the math for a realistic day. Say your agent handles 40 messages, and about half of them benefit from memory context.
MEMORY.md approach:
- 3,000 tokens loaded into every message
- 40 messages Γ 3,000 input tokens = 120,000 tokens/day on memory alone
- At Claude Sonnet pricing ($3/M input tokens): $0.36/day
- Monthly: ~$10.80
MemoClaw approach:
- 20 recalls/day (only when needed) Γ $0.005 = $0.10/day
- Each recall returns ~100-200 tokens instead of 3,000
- Context token savings: ~100 tokens Γ 20 = 2,000 tokens vs 120,000
- Monthly recall cost: ~$3.00
- Monthly context savings: ~$10.44
The net savings depend on how big your MEMORY.md is and how chatty your agent is. But the pattern holds: selective recall beats full-file loading every time.
For agents with large memory files (8,000+ tokens) or high message volumes, the gap widens fast.
Itβs not just cost β itβs speed
Token count affects latency. More input tokens means longer time-to-first-token. If youβve noticed your agent getting slower over time, your growing MEMORY.md might be part of it.
Shaving 2,800 tokens off every request wonβt make responses instant, but it helps. Especially on models that charge more and think longer with larger contexts.
How to set this up
Install the MemoClaw skill:
clawhub install anajuliabit/memoclaw
Then update your agentβs instructions. Instead of:
Read MEMORY.md at session start.
Use something like:
Use memoclaw recall to fetch relevant context when you need it.
Don't load all memories at once. Query for what's relevant to the current task.
Your agent now has store and recall tools. It calls recall when it needs context and store when it learns something new. No file reading, no bulk loading.
What about the free tier?
MemoClaw gives you 100 free API calls. Store and recall each cost one call. If youβre doing 20 recalls a day, youβll burn through the free tier in about 5 days.
After that, itβs pay-per-request with USDC on Base. No subscriptions, no monthly minimums. You pay for what you use via x402 β the payment happens automatically with each request.
At $0.005 per recall, even heavy usage stays cheap. 1,000 recalls = $5.00.
# Check where you stand
memoclaw status
The tradeoff
There is one. MEMORY.md is free to read β itβs just a file. MemoClaw costs $0.005 per recall. If your agent makes a lot of recalls per message, the cost could theoretically exceed the context-window savings.
In practice, this rarely happens. A well-configured agent makes 0-2 recalls per message. The context savings almost always outweigh the recall cost, especially as your memory store grows. A 200-line MEMORY.md costs you tokens every message whether you need those memories or not. A 200-memory MemoClaw store costs nothing until you query it.
The other tradeoff: latency. A recall takes ~200-400ms. Thatβs an extra network round trip your agent didnβt have before. For most use cases, this is invisible β the modelβs thinking time dwarfs it. But if youβre building something where every millisecond counts, itβs worth knowing.
When to stick with MEMORY.md
Honestly? If your MEMORY.md is under 500 tokens and you donβt expect it to grow much, the file approach is fine. The savings from MemoClaw kick in when your memory gets big enough that loading it all becomes wasteful.
The crossover point is roughly 1,000-1,500 tokens of memory. Below that, the simplicity of a flat file wins. Above that, youβre paying a growing tax on every message for context your agent mostly ignores.
Your agentβs context window is expensive real estate. MEMORY.md treats it like a storage unit β cram everything in and sort through it later. MemoClaw treats it like a search engine β ask for what you need, get whatβs relevant. The difference shows up in your API bill and your response times.