we have run agent sessions using coder and documenter which have feiled to make edits to documentation files in @project even
though they have access to the whole /workspace folder. Can we find out why?
```
Response:
```
Summary: Root Cause Identified
Both coder and documenter agents are properly configured with write and edit tools. The actual failure was:
### Error
```
400 Reasoning is mandatory for this endpoint and cannot be disabled.
```
### Location
agent/extensions/agent-team.ts line 239 forces --thinking "off" for all sub-agents:
```typescript
const args = [
"--mode", "json",
"-p",
"--no-extensions",
"--model", model,
"--tools", state.def.tools,
"--thinking", "off", // ⛔ BLOCKS models that require reasoning
"--append-system-prompt", state.def.systemPrompt,
"--session", agentSessionFile,
];
```
### Why this breaks
- The configured model (stepfun/step-3.5-flash) requires reasoning enabled
- The agent fails immediately (1 second) with HTTP 400 before attempting any file operations
- The dispatcher reports "done" but no edits were made
### Evidence
Both session files in .pi/agent-sessions/ show identical error traces with stopReason: "error" and the 400 message.
────────────────────────────────────────────────────────────────────────────────
Recommended Fix
Edit agent/extensions/agent-team.ts — either:
Option A (simplest): Remove the --thinking "off" line entirely → models use their default reasoning level
Option B: Change to --thinking "minimal" → enables reasoning at lowest cost
Option C: Make thinking level configurable per agent via frontmatter (e.g., add thinking: minimal to agent definitions)
Would you like me to guide you through implementing Option A or B? Note: As the dispatcher agent, I don't have direct file edit capability, but I can explain exactly what change to make.
```
Hope this is helpful in some way :)
I thought you may be interested in this:
My prompt: