Repository navigation
[BUG] Un-controllable Token Exceed with MCP results #648
Description
Problem (one or two sentences)
The conversation will get stuck when MCP tools return a large amount of context.
- with “Compression API failed: OpenAI completion error: 400 request (359746 tokens) exceeds the available context size (128000 tokens), try increasing it”
Context (who is affected and when)
N/A
Reproduction steps
- Clone a rather large git repo
- Activate "Git Tools" from "Zoo Marketplace - MCP"
- Ask Zoo to check the diff and status of this git repo
- Zoo will use the MCP tool for the task
- The conversation gets stuck with a compression error
Expected result
Run normally with either trunc or compressed MCP result
Actual result
“Compression API failed: OpenAI completion error: 400 request (359746 tokens) exceeds the available context size (128000 tokens), try increasing it”
Variations tried (optional)
No response
App Version
3.60.0
API Provider (optional)
OpenAI Compatible
Model Used (optional)
Qwen3.6-27B
Zoo Code Task Links (optional)
No response
Activity
pajitosingh commentedon Jun 18, 2026
I can confirm. This happens with html_get use with a browser mcp (playwright) as well. A large html dump will take the context over 1M sometimes and then the session is borked.
Awilen-Bernkastel commentedon Sep 14, 2026
Adding to this: my own workflow first compacts fine, then the subsequent compaction runs try to reuse the full context from before compaction. This leads to a silly situation in which a session tries to compact a million-tokens worth of conversation from a 128k window:
Condensing API call failed: OpenAI completion error: 400 request (1009019 tokens) exceeds the available context size (128000 tokens), try increasing it(Yes, somehow this is still working out fine for my purpose, despite the context window crops.)This didn't come from a massive MCP call result filling the context window, just normal usage. This may be another bug I could describe as "the compaction algorithm keeps reusing the full conversation instead of previous compaction results."