Evaluation monitors automate recurring evaluations. Instead of manually creating eval runs, a monitor saves your target type, metrics, filters, sampling rate, and cadence, then creates eval runs automatically in the background. Use monitors for recurring workflows such as:Documentation Index
Fetch the complete documentation index at: https://docs.pandaprobe.com/llms.txt
Use this file to discover all available pages before exploring further.
- Daily production trace quality checks
- Weekly session reliability audits
- Regression monitoring after releases
- Continuous evaluation of high-value users, tags, or environments
Dashboard setup
Create monitors from the Evaluations tab in the PandaProbe dashboard.Configure the monitor
Add a name, choose the target type (
TRACE or SESSION), select metrics, and add filters that define the traces or sessions the monitor should evaluate.Set the cadence
Choose how often the monitor should create a new eval run. Cadence controls the recurring schedule.
Monitor fields
When creating a monitor from the dashboard, configure:- Name: a human-readable label for the monitor.
- Target type:
TRACEfor trace evaluation orSESSIONfor session evaluation. - Metrics: the trace-level or session-level metrics to run.
- Filters: the matching traces or sessions to evaluate.
- Sampling rate: the portion of matching data to evaluate on each run.
- Cadence: how often PandaProbe creates a new eval run.
- Model: optional model selection for LLM-as-judge metrics.
- Customize signal weights: optional for session monitors.
Filters
- Trace monitors
- Session monitors
Trace monitors can filter by fields such as Started after, Started before, Status, Trace ID, Session ID, User, and Tags.
Sampling rate
Sampling rate controls what portion of matching data is evaluated each time the monitor runs. For example:1.0evaluates all matching traces or sessions.0.5evaluates 50% of matching traces or sessions.0.1evaluates 10% of matching traces or sessions.
API setup
You can also create and manage monitors through the API.Create a monitor
Request fields
| Field | Type | Required | Description |
|---|---|---|---|
name | string | Yes | Human-readable label for the monitor |
target_type | string | Yes | "TRACE" or "SESSION" |
metrics | string[] | Yes | Metric names to run on each scheduled eval |
filters | object | No | Scope the data the monitor evaluates |
cadence | string | Yes | Firing schedule |
sampling_rate | float | No | Fraction of matching data to evaluate per run |
model | string | No | LLM model override for judge calls |
only_if_changed | boolean | No | Skip the run if no new data has arrived since the previous run |
signal_weights | object | No | Override signal weights for session monitors |
Session monitor example
Cadence options
Monitors support predefined intervals and custom cron expressions.| Value | Schedule |
|---|---|
every_6h | Every 6 hours |
daily | Once per day |
weekly | Once per week |
cron:0 3 * * * | Daily at 3:00 AM UTC |
cron:0 6 * * 1-5 | Weekdays at 6:00 AM UTC |
cron:0 */4 * * * | Every 4 hours |
The only_if_changed flag
When only_if_changed is true, PandaProbe skips a scheduled run if no new traces or sessions have arrived since the previous run. This helps avoid re-evaluating the same data unnecessarily.
Set it to false when you want the monitor to run on every cadence tick, even if the underlying data has not changed.
Manage monitors
Monitors have two states:| Status | Description |
|---|---|
ACTIVE | The monitor runs on schedule and creates eval runs at each cadence tick |
PAUSED | The schedule is suspended and no new runs are created |
trigger to create an immediate eval run from a monitor without waiting for the next scheduled cadence.
Next steps
Run Evaluations via UI
Create one-off trace and session eval runs from the dashboard.
Run Evaluations via API
Create and manage eval runs programmatically.

