Inferensys

Prompt

Dashboard-Ready Metric Extraction Prompt Template

A practical prompt playbook for extracting structured, dashboard-ready metrics from raw production trace spans using a validated prompt template.
Analytics team reviewing AI metrics dashboard on large monitor, KPIs visible, modern data-driven office setup.
PROMPT PLAYBOOK

When to Use This Prompt

Defines the ideal scenario, user, and prerequisites for extracting structured metrics from raw trace spans, and clarifies when this prompt is not the right tool.

This prompt is designed for platform engineers and AI SREs who need to convert raw, unstructured trace spans into structured, time-series data points suitable for dashboards like Grafana or Datadog. The core job-to-be-done is reliable, repeatable metric extraction and normalization. Use it when you have a batch of trace spans and need to produce a consistent set of metrics, aggregation windows, and dimension labels that conform to a predefined naming convention. The ideal user has a solid understanding of their observability data and a clear target schema for their metrics.

Before using this prompt, you must have a defined [OUTPUT_SCHEMA] that specifies the exact metric names, types (gauge, counter, histogram), and label dimensions you expect. The prompt enforces this schema, rejecting extractions that don't conform. This is not a prompt for ad-hoc data exploration or real-time alert evaluation. It will not perform threshold checks or anomaly detection; its sole purpose is extraction and normalization. For real-time alerting, pair this prompt's output with a separate rules engine or use a dedicated alert condition prompt. Do not use this prompt if your trace data contains sensitive user information that hasn't been redacted, as the prompt processes the raw text directly.

To get started, gather a representative sample of your raw trace spans and your target metric schema. The next section provides the copy-ready prompt template. After integrating it, you will need to build a validation harness to check the output against your schema before sending data to your dashboarding system. Avoid the temptation to add alerting logic directly into this prompt; keeping its responsibility narrow ensures predictable, testable behavior in your monitoring pipeline.

PRACTICAL GUARDRAILS

Use Case Fit

This prompt template extracts structured, time-series-ready metrics from raw trace spans for dashboarding. It works best when you have consistent span structures and a known metric taxonomy. It fails when traces are unstructured, naming conventions are absent, or the extraction target is a narrative summary rather than a numeric data point.

01

Good Fit: Structured Span Ingestion

Use when: you have a steady stream of spans with predictable attributes, duration, and status fields. Guardrail: validate input span schema before extraction to prevent silent null outputs.

02

Bad Fit: Unstructured Log Analysis

Avoid when: the source data is free-text log lines without a defined span format. Guardrail: route unstructured text to a classification or extraction prompt first; this template requires pre-normalized trace data.

03

Required Input: Metric Taxonomy

Risk: without a defined list of metric names, the model invents ad-hoc metrics that break dashboard queries. Guardrail: always supply a [METRIC_CATALOG] with allowed names, aggregation types, and dimension keys.

04

Operational Risk: Cardinality Explosion

Risk: high-cardinality dimensions (e.g., raw user IDs) produce too many unique time series, overwhelming TSDBs. Guardrail: enforce a [DIMENSION_LIMITS] block that restricts dimensions to low-cardinality labels like service.name or status_code.

05

Operational Risk: Aggregation Window Misalignment

Risk: mismatched aggregation windows between extraction and dashboard queries cause misleading spikes or flatlines. Guardrail: explicitly pass [AGGREGATION_WINDOW_SECONDS] and validate that output timestamps align to window boundaries.

06

Bad Fit: Narrative Incident Summaries

Avoid when: the goal is a human-readable incident report rather than numeric data points. Guardrail: use a trace summarization prompt for stakeholder reports; this template targets machine-readable metric payloads for dashboard ingestion.

PROMPT PLAYBOOK

Copy-Ready Prompt Template

A reusable prompt that extracts structured, dashboard-ready metrics from raw trace spans for ingestion into Grafana, Datadog, or custom monitoring systems.

This template converts unstructured or semi-structured trace data into a strict time-series metric format. It is designed for platform engineers who need to pipe production observability data into dashboards without writing brittle parsing code. The prompt enforces metric naming conventions, aggregation windows, and dimension labels so the output can be directly consumed by a metrics API or collector. Use this when you have raw span JSON and need consistent, validated metric points. Do not use it for real-time alerting logic—that belongs in the alert condition definition prompts.

text
You are a production metrics extraction engine. Your task is to convert raw trace spans into structured time-series metric points suitable for dashboard ingestion.

INPUT TRACE SPANS:
[RAW_TRACE_SPANS]

METRIC DEFINITIONS TO EXTRACT:
[METRIC_DEFINITIONS]

AGGREGATION WINDOW:
[AGGREGATION_WINDOW_SECONDS]

DIMENSION LABELS TO INCLUDE:
[DIMENSION_LABELS]

OUTPUT SCHEMA (strict JSON array):
[
  {
    "metric_name": "string (must match [METRIC_NAMING_CONVENTION])",
    "timestamp": "ISO 8601 UTC",
    "value": number,
    "aggregation": "sum | avg | p50 | p95 | p99 | count | rate",
    "window_start": "ISO 8601 UTC",
    "window_end": "ISO 8601 UTC",
    "dimensions": {
      "[DIMENSION_LABELS]": "string"
    },
    "source_span_ids": ["string"],
    "confidence": 0.0-1.0
  }
]

CONSTRAINTS:
[CONSTRAINTS]

EXAMPLES:
[FEW_SHOT_EXAMPLES]

Before outputting, validate:
1. Every metric_name matches the [METRIC_NAMING_CONVENTION] pattern.
2. Timestamps fall within the aggregation window.
3. Aggregation method matches the metric definition.
4. All required dimension labels are present and non-empty.
5. source_span_ids reference spans present in the input.
6. confidence reflects data completeness (1.0 = all expected spans present, <1.0 = gaps).

If validation fails for any metric point, exclude it and include it in a separate "rejected_points" array with a "rejection_reason" field.

Adapt this template by replacing each square-bracket placeholder with your production data. [RAW_TRACE_SPANS] should contain the JSON array of span objects from your tracing system. [METRIC_DEFINITIONS] specifies which metrics to extract—for example, latency_ms from span duration, token_count from span attributes, or tool_call_error from span status. [AGGREGATION_WINDOW_SECONDS] defines the time bucket (e.g., 60 for per-minute metrics). [DIMENSION_LABELS] lists the span attributes to preserve as dimensions, such as model_version, prompt_id, or session_id. [CONSTRAINTS] can include value ranges, required label combinations, or exclusion rules. [FEW_SHOT_EXAMPLES] should show 2-3 correct input-output pairs covering normal spans, error spans, and edge cases like missing attributes. Wire the output into your metrics pipeline with a JSON Schema validator that rejects any point violating the naming convention or missing required dimensions before ingestion.

IMPLEMENTATION TABLE

Prompt Variables

Inputs the prompt needs to extract structured metrics from raw trace spans. Validate each before sending to avoid schema violations or silent null fields in your dashboard.

PlaceholderPurposeExampleValidation Notes

[TRACE_SPANS]

Raw trace data containing span events, timestamps, and metadata

{"spans": [{"trace_id": "abc123", "name": "llm/completion", "duration_ms": 450, "attributes": {"tokens": 1200}}]}

Must be valid JSON array. Reject if empty or missing required span fields (trace_id, name, duration_ms). Parse check required.

[METRIC_SCHEMA]

Target metric definitions with naming conventions, aggregation rules, and dimension labels

{"metrics": [{"name": "llm.latency.p95", "aggregation": "p95", "field": "duration_ms", "dimensions": ["model", "prompt_version"]}]}

Validate against metric naming convention (e.g., OpenTelemetry). Reject if metric names contain spaces or unsupported aggregation functions. Schema check required.

[AGGREGATION_WINDOW]

Time window for metric rollup in seconds or ISO 8601 duration

300 or "PT5M"

Must be positive integer or valid ISO 8601 duration string. Reject zero or negative values. Parse check with retry on format mismatch.

[DIMENSION_FILTERS]

Optional key-value filters to scope metric extraction to specific trace subsets

{"model": "claude-3-opus", "prompt_version": "v2.4.1"}

Allow null or empty object. If provided, validate filter keys exist in span attributes. Warn on unmatched filters but do not reject. Null allowed.

[OUTPUT_FORMAT]

Target output structure for dashboard ingestion (e.g., Prometheus exposition, Datadog series, InfluxDB line protocol)

"datadog_series"

Must match one of supported enum values: prometheus_exposition, datadog_series, influxdb_line, openmetrics. Reject unrecognized formats. Enum check required.

[TIMESTAMP_FIELD]

Span field to use as the metric timestamp source

"start_time_unix_nano"

Must reference a valid numeric timestamp field present in span structure. Reject if field missing from all spans. Field existence check required.

[CONFIDENCE_THRESHOLD]

Minimum confidence score for including a span in metric calculation (0.0 to 1.0)

0.8

Must be float between 0.0 and 1.0 inclusive. Reject out-of-range values. If spans lack confidence scores, set to null to disable filtering. Range check required.

PROMPT PLAYBOOK

Implementation Harness Notes

How to wire the metric extraction prompt into a production observability pipeline with validation, retries, and dashboard integration.

This prompt is designed to be called by an automated pipeline, not a human chat interface. The primary integration point is a scheduled job or a webhook that fires after trace ingestion. The harness must supply the raw trace span data as [INPUT], the target metric schema as [OUTPUT_SCHEMA], and the aggregation window as [CONSTRAINTS]. The model's response should be treated as a structured payload that requires validation before it reaches any time-series database or dashboard.

The implementation harness should follow a strict validate-then-ingest pattern. After receiving the model's JSON output, apply a schema validator that checks for required fields (metric_name, value, timestamp, dimensions), enforces the snake_case naming convention defined in [OUTPUT_SCHEMA], and rejects any metric name that does not match the allowed prefix list. If validation fails, the harness should retry the prompt once with the validation error message appended to [CONSTRAINTS]. If the second attempt also fails, log the raw trace span, the model's malformed output, and the validation errors to a dead-letter queue for manual review. Never ingest unvalidated metrics into Grafana or Datadog.

For model choice, prefer a model with strong JSON mode and low latency, such as gpt-4o-mini or claude-3-haiku, since this prompt runs on a high-volume trace stream. Set temperature=0 to maximize output determinism. The harness should also implement idempotency keys based on trace_id and aggregation_window to prevent duplicate metric points if the pipeline retries a batch. Finally, expose a prompt_version label on every emitted metric so dashboard queries can isolate regressions caused by prompt changes. Do not use this prompt for real-time alerting thresholds; it is designed for near-real-time dashboard population where a 60-second processing delay is acceptable.

IMPLEMENTATION TABLE

Expected Output Contract

Schema contract for a single extracted metric data point. Use this to validate the model's output before ingestion into a time-series database or dashboard.

Field or ElementType or FormatRequiredValidation Rule

metric_name

string (snake_case)

Must match regex ^[a-z][a-z0-9_]*(?:_seconds|_bytes|_ratio|_total|_count|_errors)?$

metric_value

number (float64)

Must be finite; reject NaN, Inf, or -Inf

timestamp

string (RFC 3339)

Must parse with DateTimeFormatter.ISO_OFFSET_DATE_TIME; reject if in the future by more than 5 minutes

aggregation_window_seconds

integer

Must be positive; typical values: 60, 300, 3600; reject if 0 or negative

dimensions

object (map[string]string)

Keys must be snake_case; values must be non-empty strings; max 10 key-value pairs

trace_span_id

string (hex)

If present, must match regex ^[a-f0-9]{16}$; null allowed

confidence

number (float)

If present, must be between 0.0 and 1.0 inclusive; null allowed; values below 0.7 should trigger a review flag

PRACTICAL GUARDRAILS

Common Failure Modes

Metric extraction from raw traces fails in predictable ways. These are the most common failure modes when turning unstructured span data into dashboard-ready time-series points, and how to prevent them before they corrupt your monitoring dashboards.

01

Schema Drift in Output Fields

What to watch: The model changes field names, nests objects differently, or omits required dimensions across extraction runs. A metric that was p50_latency_ms becomes p50_latency or moves under a metrics sub-object, breaking dashboard queries. Guardrail: Validate every extraction response against a strict JSON Schema before ingestion. Reject and retry any payload that fails field-level type and required-field checks. Log schema violations by trace ID for debugging.

02

Aggregation Window Boundary Errors

What to watch: The model misaligns time buckets, double-counts spans that cross window boundaries, or produces aggregation windows that don't match your dashboard's time range. A 5-minute rollup might include spans from minute 6, or a 1-hour window might silently drop the first 3 minutes of data. Guardrail: Post-process extracted timestamps against a deterministic bucketing function in application code. Never trust the model to perform boundary arithmetic. Compare bucket counts against raw span counts as a consistency check.

03

Dimension Label Inconsistency

What to watch: The model normalizes dimension values unpredictably—model:gpt-4o becomes model:gpt-4o-2024-08-06 in some extractions and model:gpt-4o in others, creating fragmented time-series that don't aggregate correctly. Same root cause appears in error type labels, tool names, and environment tags. Guardrail: Maintain an allowlist of known dimension values and map extracted labels to canonical forms before ingestion. Flag unmapped labels for human review rather than silently creating new dimension values.

04

Null Handling and Missing Spans

What to watch: When a trace has no error spans, no tool calls, or no retrieval steps, the model may omit the metric entirely instead of emitting a zero value. Dashboards then show gaps instead of zeros, breaking alert thresholds and trend calculations. Guardrail: Define a complete metric inventory with default zero values for every expected metric. After extraction, backfill any missing metric keys with explicit zeros and log which traces produced nulls versus which metrics were genuinely absent.

05

Token Count Inflation from Prompt Overhead

What to watch: The extraction prompt itself consumes significant tokens when processing large traces, and the model includes its own prompt tokens in the reported token consumption metrics. This creates a positive feedback loop where monitoring inflates the very cost it's measuring. Guardrail: Strip extraction prompt tokens from reported metrics by subtracting the known prompt token count. Tag extracted metrics with source:extraction to distinguish them from application-level token consumption in downstream dashboards.

06

High-Cardinality Dimension Explosion

What to watch: The model extracts unique dimension values for every trace—session IDs, user IDs, or raw span IDs—as metric labels. This creates high-cardinality time-series that overwhelm time-series databases and make dashboards unusably slow. Guardrail: Restrict extracted dimensions to a pre-approved list of low-cardinality labels. Use application-level aggregation to roll up high-cardinality identifiers into categories before metric emission. Validate cardinality in staging before production rollout.

IMPLEMENTATION TABLE

Evaluation Rubric

Test the extracted metric payload against these criteria before wiring the prompt into a dashboard pipeline. Each row targets a specific failure mode observed in production metric extraction.

CriterionPass StandardFailure SignalTest Method

Schema compliance

Output parses as valid JSON matching [OUTPUT_SCHEMA] exactly; no extra keys, no missing required fields.

JSON parse error or schema validation failure on required fields like metric_name, value, or timestamp.

Validate against [OUTPUT_SCHEMA] using a JSON Schema validator in a pre-commit hook or CI step.

Metric naming convention

Every metric_name matches the pattern defined in [NAMING_CONVENTION] (e.g., namespace.service.metric_unit).

Metric name contains spaces, unsupported characters, or omits the required namespace prefix.

Run a regex check on all metric_name fields against the pattern supplied in [NAMING_CONVENTION].

Timestamp format and range

All timestamp values are ISO 8601 UTC and fall within the [TRACE_WINDOW_START] to [TRACE_WINDOW_END] range.

Unix epoch timestamps, non-UTC offsets, or timestamps outside the provided trace window.

Parse each timestamp with a standard library and assert it is within the expected window.

Value type and precision

value is a number; unit is a non-empty string from the allowed [UNIT_ENUM] list.

value is a string, boolean, or null; unit is missing or not in the approved enum.

Check typeof value === 'number' and assert unit is in the [UNIT_ENUM] set.

Dimension label consistency

All entries for a given metric_name share the same set of dimension keys in labels.

Dimension keys vary across data points for the same metric (e.g., one point has host and another has pod).

Group output by metric_name and assert that the set of keys in labels is identical across the group.

Aggregation window alignment

aggregation_window_seconds is a positive integer and aligns with [AGGREGATION_WINDOW] from the prompt.

Window is zero, negative, or a different value than the requested aggregation window.

Assert aggregation_window_seconds === [AGGREGATION_WINDOW] for every data point.

Source trace grounding

source_trace_id is a non-empty string present in the provided [TRACE_INPUT].

Missing source_trace_id, or an ID that does not appear in the input trace spans.

Collect all trace IDs from [TRACE_INPUT] and assert each output source_trace_id is in that set.

No hallucinated metrics

Every metric value can be recalculated from the raw spans in [TRACE_INPUT].

A metric appears in the output that has no corresponding span data to support it.

For each output metric, verify the calculation against the raw span data using a deterministic script.

ADAPTATION OPTIONS

Adapt This Prompt

How to adapt

Add strict schema validation against your observability backend's ingestion format. Replace [OUTPUT_SCHEMA] with the exact payload structure expected by Grafana, Datadog, or your custom dashboard. Include aggregation window parameters: "window_seconds": [WINDOW_SIZE], "aggregation": "[SUM|AVG|P95|COUNT]". Add retry logic with schema repair instructions in the retry prompt. Wire in a post-extraction validator that checks metric naming conventions before ingestion.

Watch for

  • Silent format drift when model outputs valid JSON but wrong field types
  • Cardinality explosions from unbounded dimension values
  • Missing human review step for metrics that trigger alerts
  • Aggregation window misalignment causing dashboard gaps
Prasad Kumkar

About the author

Prasad Kumkar

CEO & MD, Inference Systems

Prasad Kumkar is the CEO & MD of Inference Systems and writes about AI systems architecture, LLM infrastructure, model serving, evaluation, and production deployment. Over 5+ years, he has worked across computer vision models, L5 autonomous vehicle systems, and LLM research, with a focus on taking complex AI ideas into real-world engineering systems.

His work and writing cover AI systems, large language models, AI agents, multimodal systems, autonomous systems, inference optimization, RAG, evaluation, and production AI engineering.