read-eval-logs
Testing & QualityView and analyse Inspect evaluation log files using the Python API. Trigger whenever you need to look at a .eval file yourself without using pre-written scripts.
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Analysing Eval Log Files
This skill covers how to view and analyse Inspect evaluation log files using the Python API and CLI commands.
Quick Reference
CLI Commands
# List all logs in the default log directory (./logs or INSPECT_LOG_DIR)
uv run inspect log list --json
# List logs with specific status
uv run inspect log list --json --status success
uv run inspect log list --json --status error
# List retryable logs (error/cancelled without subsequent success)
uv run inspect log list --json --retryable
# Dump a log file as JSON (works with any format: .eval or .json)
uv run inspect log dump <log_file_path>
# Convert between log formats
uv run inspect log convert source.json --to eval --output-dir log-output
uv run inspect log convert logs/ --to eval --output-dir logs-eval
# Get JSON schema for log files
uv run inspect log schema
Interactive Log Viewer
# Start the interactive log viewer (updates automatically)
uv run inspect view
Python API
Key Imports
from inspect_ai.log import (
# Listing and reading
list_eval_logs,
read_eval_log,
read_eval_log_sample,
read_eval_log_samples,
read_eval_log_sample_summaries,
# Writing
write_eval_log,
# Utilities
retryable_eval_logs,
recompute_metrics,
resolve_sample_attachments,
# Types
EvalLog,
EvalLogInfo,
EvalSample,
EvalSampleSummary,
)
Listing Logs
# List all logs in default directory
logs = list_eval_logs()
# List logs in a specific directory
logs = list_eval_logs(log_dir="./experiment-logs")
# Filter by format
logs = list_eval_logs(formats=["eval"]) # Only .eval files
# Filter with a custom function (receives header-only EvalLog)
logs = list_eval_logs(filter=lambda log: log.status == "success")
# Non-recursive listing
logs = list_eval_logs(recursive=False)
Reading Logs
# Read full log
log = read_eval_log("path/to/logfile.eval")
# Read header only (fast, excludes samples)
log = read_eval_log("path/to/logfile.eval", header_only=True)
# Read with attachments resolved
log = read_eval_log("path/to/logfile.eval", resolve_attachments=True)
Reading Samples
# Read a single sample by ID and epoch
sample = read_eval_log_sample("path/to/logfile.eval", id=42, epoch=1)
# Read a single sample by UUID
sample = read_eval_log_sample("path/to/logfile.eval", uuid="sample-uuid")
# Stream all samples (memory efficient - one at a time)
for sample in read_eval_log_samples("path/to/logfile.eval"):
process(sample)
# Stream samples from incomplete logs
for sample in read_eval_log_samples("path/to/logfile.eval", all_samples_required=False):
process(sample)
# Read sample summaries (fast, includes scoring info)
summaries = read_eval_log_sample_summaries("path/to/logfile.eval")
Filtering Samples
# Read only samples with errors using summaries for filtering
errors = []
for summary in read_eval_log_sample_summaries(log_file):
if summary.error is not None:
errors.append(
read_eval_log_sample(log_file, summary.id, summary.epoch)
)
EvalLog Structure
The EvalLog object contains:
| Field | Type | Description |
|---|---|---|
version | int | File format version (currently 2) |
status | str | "started", "success", "cancelled", or "error" |
eval | EvalSpec | Task, model, creation time, config |
plan | EvalPlan | Solvers and generation config |
results | EvalResults | Aggregate scores and metrics |
stats | EvalStats | Runtime, model usage statistics |
error | EvalError | Error info if status == "error" |
samples | list[EvalSample] | Individual samples (if not header_only) |
reductions | list[EvalSampleReductions] | Multi-epoch reductions |
location | str | URI where log was read from |
Always Check Status
log = read_eval_log("path/to/logfile.eval")
if log.status == "success":
# Safe to analyse results
for score in log.results.scores:
print(f"{score.name}: {score.metrics}")
EvalSample Structure
Each sample contains:
| Field | Type | Description |
|---|---|---|
id | int | str | Unique sample ID |
epoch | int | Epoch number |
input | str | list[ChatMessage] | Sample input |
target | str | list[str] | Expected target(s) |
messages | list[ChatMessage] | Full conversation history |
output | ModelOutput | Model's output |
scores | dict[str, Score] | Scores from scorers |
metadata | dict[str, Any] | Sample metadata |
store | dict[str, Any] | State at end of execution |
events | list[Event] | Transcript events |
error | EvalError | Error if sample failed |
total_time | float | Total sample runtime |
model_usage | dict[str, ModelUsage] | Token usage |
Common Analysis Patterns
Get Aggregate Metrics
log = read_eval_log(log_file, header_only=True)
if log.results:
for score in log.results.scores:
print(f"Scorer: {score.name}")
for metric_name, metric in score.metrics.items():
print(f" {metric_name}: {metric.value}")
Analyse Failed Samples
log = read_eval_log(log_file)
if log.samples:
failed = [s for s in log.samples if s.error is not None]
for sample in failed:
print(f"Sample {sample.id}: {sample.error.message}")
Extract Model Usage
log = read_eval_log(log_file, header_only=True)
for model, usage in log.stats.model_usage.items():
print(f"{model}: {usage.input_tokens} in, {usage.output_tokens} out")
Compare Multiple Runs
logs = list_eval_logs(filter=lambda l: l.eval.task == "my_task")
for log_info in logs:
log = read_eval_log(log_info, header_only=True)
if log.results and log.results.scores:
accuracy = log.results.scores[0].metrics.get("accuracy")
print(f"{log.eval.model}: {accuracy.value if accuracy else 'N/A'}")
Find Retryable Logs
all_logs = list_eval_logs()
retryable = retryable_eval_logs(all_logs)
for log_info in retryable:
print(f"Can retry: {log_info.name}")
Log File Formats
| Type | Description |
|---|---|
.eval | Binary format, ~1/8 size of JSON, fast incremental access |
.json | Text format, human-readable, slower for large files |
Both formats are fully supported by the API and can be intermixed.
Working with Large Logs
For logs too large to fit in memory:
- Use
.evalformat - supports compression and incremental access - Read header only -
read_eval_log(log_file, header_only=True) - Stream samples -
read_eval_log_samples()yields one at a time - Use summaries -
read_eval_log_sample_summaries()for quick overview
Modifying Logs
# Read, modify, and write back
log = read_eval_log(log_file)
# ... modify log ...
write_eval_log(log) # Uses log.location automatically
# Write to a new location
write_eval_log(log, location="new_path.eval")
# Recompute metrics after score edits
recompute_metrics(log)
write_eval_log(log)
Environment Variables
| Variable | Description |
|---|---|
INSPECT_LOG_DIR | Default log directory (default: ./logs) |
INSPECT_EVAL_LOG_FILE_PATTERN | Log filename pattern (e.g., {task}_{model}_{id}) |
Related Tools
- Inspect Scout - Transcript analysis
- Inspect Viz - Data visualization
- Log Dataframes - Extract pandas DataFrames from logs (see
inspect_ai.analysis)