website/docs/user-guide/features/batch-processing.md
Batch processing lets you run the Hermes agent across hundreds or thousands of prompts in parallel, generating structured trajectory data. This is primarily used for training data generation — producing ShareGPT-format trajectories with tool usage statistics that can be used for fine-tuning or evaluation.
The batch runner (batch_runner.py) processes a JSONL dataset of prompts, running each through a full agent session with tool access. Each prompt gets its own isolated environment. The output is structured trajectory data with full conversation history, tool call statistics, and reasoning coverage metrics.
# Basic batch run
python batch_runner.py \
--dataset_file=data/prompts.jsonl \
--batch_size=10 \
--run_name=my_first_run \
--model=anthropic/claude-sonnet-4.6 \
--num_workers=4
# Resume an interrupted run
python batch_runner.py \
--dataset_file=data/prompts.jsonl \
--batch_size=10 \
--run_name=my_first_run \
--resume
# List available toolset distributions
python batch_runner.py --list_distributions
:::tip Predictable cost at scale
Batch runs spin up many concurrent agent sessions, each making model calls and tool calls. A Nous Portal subscription bundles model access plus web search, image gen, TTS, and cloud browsers under one bill — useful when you want stable cost-per-trajectory without juggling rate limits across five vendor accounts. Set up with hermes setup --portal, then point --model at a Nous model.
:::
The input dataset is a JSONL file (one JSON object per line). Each entry must have a prompt field:
{"prompt": "Write a Python function that finds the longest palindromic substring"}
{"prompt": "Create a REST API endpoint for user authentication using Flask"}
{"prompt": "Debug this error: TypeError: cannot unpack non-iterable NoneType object"}
Entries can optionally include:
image or docker_image: A container image to use for this prompt's sandbox (works with Docker, Modal, and Singularity backends)cwd: Working directory override for the task's terminal session| Parameter | Default | Description |
|---|---|---|
--dataset_file | (required) | Path to JSONL dataset |
--batch_size | (required) | Prompts per batch |
--run_name | (required) | Name for this run (used for output dir and checkpointing) |
--distribution | "default" | Toolset distribution to sample from |
--model | claude-sonnet-4.6 | Model to use |
--base_url | https://openrouter.ai/api/v1 | API base URL |
--api_key | (env var) | API key for model |
--max_turns | 10 | Maximum tool-calling iterations per prompt |
--num_workers | 4 | Parallel worker processes |
--resume | false | Resume from checkpoint |
--verbose | false | Enable verbose logging |
--max_samples | all | Only process first N samples from dataset |
--max_tokens | model default | Maximum tokens per model response |
| Parameter | Description |
|---|---|
--providers_allowed | Comma-separated providers to allow (e.g., "anthropic,openai") |
--providers_ignored | Comma-separated providers to ignore (e.g., "together,deepinfra") |
--providers_order | Comma-separated preferred provider order |
--provider_sort | Sort by "price", "throughput", or "latency" |
| Parameter | Description |
|---|---|
--reasoning_effort | Effort level: none, minimal, low, medium, high, xhigh |
--reasoning_disabled | Completely disable reasoning/thinking tokens |
| Parameter | Description |
|---|---|
--ephemeral_system_prompt | System prompt used during execution but NOT saved to trajectories |
--log_prefix_chars | Characters to show in log previews (default: 100) |
--prefill_messages_file | Path to JSON file with prefill messages for few-shot priming |
Each prompt gets a randomly sampled set of toolsets from a distribution. This ensures training data covers diverse tool combinations. Use --list_distributions to see all available distributions.
In the current implementation, distributions assign a probability to each individual toolset. The sampler flips each toolset independently, then guarantees that at least one toolset is enabled. This is different from a hand-authored table of prebuilt combinations.
All output goes to data/<run_name>/:
data/my_run/
├── trajectories.jsonl # Combined final output (all batches merged)
├── batch_0.jsonl # Individual batch results
├── batch_1.jsonl
├── ...
├── checkpoint.json # Resume checkpoint
└── statistics.json # Aggregate tool usage stats
Each line in trajectories.jsonl is a JSON object:
{
"prompt_index": 42,
"conversations": [
{"from": "human", "value": "Write a function..."},
{"from": "gpt", "value": "I'll create that function...",
"tool_calls": [...]},
{"from": "tool", "value": "..."},
{"from": "gpt", "value": "Here's the completed function..."}
],
"metadata": {
"batch_num": 2,
"timestamp": "2026-01-15T10:30:00",
"model": "anthropic/claude-sonnet-4.6"
},
"completed": true,
"partial": false,
"api_calls": 3,
"toolsets_used": ["terminal", "file"],
"tool_stats": {
"terminal": {"count": 2, "success": 2, "failure": 0},
"read_file": {"count": 1, "success": 1, "failure": 0}
},
"tool_error_counts": {
"terminal": 0,
"read_file": 0
}
}
The conversations field uses a ShareGPT-like format with from and value fields. Tool stats are normalized to include all possible tools with zero defaults, ensuring consistent schema across entries for HuggingFace datasets compatibility.
The batch runner has robust checkpointing for fault tolerance:
--resume, the runner scans existing batch files and matches completed prompts by their actual text content (not just indices), enabling recovery even if the dataset order changestrajectories.jsonlbatch_*.jsonl files for completed prompts (by content matching)The batch runner applies automatic quality filtering:
<REASONING_SCRATCHPAD> or native thinking tokens) are discardedAfter completion, the runner prints comprehensive statistics:
Statistics are also saved to statistics.json for programmatic analysis.
Generate diverse tool-use trajectories for fine-tuning:
python batch_runner.py \
--dataset_file=data/coding_prompts.jsonl \
--batch_size=20 \
--run_name=coding_v1 \
--model=anthropic/claude-sonnet-4.6 \
--num_workers=8 \
--distribution=default \
--max_turns=15
Evaluate how well a model uses tools across standardized prompts:
python batch_runner.py \
--dataset_file=data/eval_suite.jsonl \
--batch_size=10 \
--run_name=eval_gpt4 \
--model=openai/gpt-4o \
--num_workers=4 \
--max_turns=10
For benchmarks requiring specific environments, each prompt can specify its own container image:
{"prompt": "Install numpy and compute eigenvalues of a 3x3 matrix", "image": "python:3.11-slim"}
{"prompt": "Compile this Rust program and run it", "image": "rust:1.75"}
{"prompt": "Set up a Node.js Express server", "image": "node:20-alpine", "cwd": "/app"}
The batch runner verifies Docker images are accessible before running each prompt.