ddnetters/langfuse-observability
langfuse-observability/SKILL.md
LLM observability with Langfuse — query traces, generations, costs, metrics, and debug LLM pipelines via the REST API
development
Updated Apr 25, 2026
$ install --global
skillsauthnpx skillsauth add ddnetters/homelab-agent-skills langfuse-observabilityInstall this skill globally with one command. Works with Claude Code, Cursor, and Windsurf.
Security Scan Results
3 of 9 scanners reported clean
Some scanners were skipped, did not run, or reported a non-clean status. Review each row below.
3
Scanners Passed
9
Scanners in report
Clean
TrivyContainer and dependency vulnerability scanner
95%
Clean
SemgrepStatic code analysis for vulnerabilities
95%
Clean
mcp-scan (Snyk)Model Context Protocol security validation
95%
Skipped
Snyk (dep)Open source security scanning
50%
Skipped
Socket.devSupply chain security analysis
50%
Skipped
VirusTotalMulti-engine malware detection
50%
Skipped
CrowdStrikeAdvanced threat intelligence
50%
Skipped
OSV-ScannerOpen Source Vulnerability database check
50%
Skipped
OWASP Dep-Check
50%
Last scanned: Apr 25, 2026, 8:40 PM55.6s1 file scanned
SKILL.md
- name:
- langfuse-observability
- description:
- LLM observability with Langfuse — query traces, generations, costs, metrics, and debug LLM pipelines via the REST API
Langfuse Observability
Langfuse is an open-source LLM observability platform. Use this skill to query traces, generations, costs, and metrics from a self-hosted or cloud Langfuse instance.
Setup
# Set your Langfuse credentials
export LANGFUSE_HOST="https://langfuse.example.com" # or https://cloud.langfuse.com
export LANGFUSE_PUBLIC_KEY="pk-lf-..."
export LANGFUSE_SECRET_KEY="sk-lf-..."
All API calls use basic auth with public key as username and secret key as password.
# Base pattern for all requests
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/<endpoint>"
Health check
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/health" | jq .
Traces
List recent traces
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/traces?limit=10&page=1" | \
jq '.data[] | {id, name, timestamp, userId, totalCost, latency, tags}'
Filter by time range
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/traces?limit=20&fromTimestamp=2026-02-01T00:00:00Z&toTimestamp=2026-02-28T23:59:59Z" | \
jq '.data[] | {id, name, timestamp, totalCost, latency}'
Filter by user or name
# By user
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/traces?limit=10&userId=USER_ID" | \
jq '.data[] | {id, name, timestamp, totalCost}'
# By trace name
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/traces?limit=10&name=TRACE_NAME" | \
jq '.data[] | {id, name, timestamp, totalCost}'
Get trace details
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/traces/TRACE_ID" | \
jq '{id, name, timestamp, userId, sessionId, totalCost, latency, tags, metadata,
observations: [.observations[] | {id, type, name, model, startTime, totalCost, usage}]}'
Get trace input/output
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/traces/TRACE_ID" | jq '{input, output}'
Generations (LLM calls)
List recent generations
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/observations?type=GENERATION&limit=10&page=1" | \
jq '.data[] | {id, name, model, startTime, totalCost, inputUsage: .usage.input, outputUsage: .usage.output}'
Filter by model
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/observations?type=GENERATION&limit=10" | \
jq '[.data[] | select(.model | test("gpt-4"))] | .[] | {id, model, totalCost}'
Get generations for a trace
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/observations?type=GENERATION&traceId=TRACE_ID" | \
jq '.data[] | {id, name, model, totalCost, usage, input, output}'
Generation details
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/observations/OBSERVATION_ID" | \
jq '{id, type, name, model, modelParameters, startTime, endTime, totalCost, usage, level, statusMessage}'
Errors and warnings
# Find errors
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/observations?level=ERROR&limit=10" | \
jq '.data[] | {id, traceId, name, model, level, statusMessage, startTime}'
# Find warnings
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/observations?level=WARNING&limit=10" | \
jq '.data[] | {id, traceId, name, model, level, statusMessage, startTime}'
Daily metrics
Cost and usage by day
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/metrics/daily?limit=7" | \
jq '.data[] | {date, traces: .countTraces, cost: .totalCost,
models: [.usage[] | {model, input: .inputUsage, output: .outputUsage, total: .totalUsage}]}'
Total cost summary
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/metrics/daily?limit=30" | \
jq '{totalCost: ([.data[].totalCost] | add), totalTraces: ([.data[].countTraces] | add),
days: (.data | length), breakdown: [.data[] | {date, cost: .totalCost, traces: .countTraces}]}'
Sessions
# List recent sessions
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/sessions?page=1&limit=10" | \
jq '.data[] | {id, createdAt, projectId}'
# Get session details
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/sessions/SESSION_ID" | jq .
Scores
# List scores
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/scores?limit=10" | \
jq '.data[] | {id, name, value, dataType, traceId, comment}'
# Scores for a specific trace
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/scores?traceId=TRACE_ID" | \
jq '.data[] | {name, value, dataType, comment}'
Docker self-hosted deployment
services:
langfuse-web:
image: langfuse/langfuse:3
ports:
- "3000:3000"
environment:
DATABASE_URL: postgresql://user:pass@postgres:5432/langfuse
NEXTAUTH_SECRET: your-secret
SALT: your-salt
ENCRYPTION_KEY: your-encryption-key
NEXTAUTH_URL: https://langfuse.example.com
AUTH_DISABLE_SIGNUP: "true"
depends_on: [postgres]
langfuse-worker:
image: langfuse/langfuse-worker:3
environment:
DATABASE_URL: postgresql://user:pass@postgres:5432/langfuse
SALT: your-salt
ENCRYPTION_KEY: your-encryption-key
postgres:
image: postgres:17
volumes:
- langfuse_pg:/var/lib/postgresql/data
environment:
POSTGRES_DB: langfuse
POSTGRES_USER: user
POSTGRES_PASSWORD: pass
Langfuse v3 also supports ClickHouse for trace storage, Redis for queuing, and MinIO for object storage.
OpenRouter integration
Send traces automatically from OpenRouter to Langfuse:
- Go to https://openrouter.ai/settings/integrations
- Enable Langfuse destination
- Set Base URL:
https://langfuse.example.com - Add Public Key and Secret Key from Langfuse Settings → API Keys
All OpenRouter LLM calls will then appear as traces in Langfuse.
Common queries
Most expensive traces this week
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/traces?limit=50&fromTimestamp=$(date -d '7 days ago' +%FT00:00:00Z)" | \
jq '[.data[] | {id, name, totalCost, timestamp}] | sort_by(-.totalCost) | .[:10]'
Model usage breakdown
curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/observations?type=GENERATION&limit=100" | \
jq '[.data[] | .model] | group_by(.) | map({model: .[0], count: length}) | sort_by(-.count)'
Error rate
ERRORS=$(curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/observations?level=ERROR&limit=1" | jq '.meta.totalItems')
TOTAL=$(curl -s -u "$LANGFUSE_PUBLIC_KEY:$LANGFUSE_SECRET_KEY" \
"$LANGFUSE_HOST/api/public/observations?limit=1" | jq '.meta.totalItems')
echo "Error rate: $ERRORS / $TOTAL"
Tips
- Always use time filters (
fromTimestamp/toTimestamp) on large queries to avoid timeouts - Pagination: responses include
meta.page,meta.limit,meta.totalItems,meta.totalPages - Timestamps use ISO 8601 format:
2026-02-10T00:00:00Z - Cost values are in USD
- Token counts are in
usage.input,usage.output,usage.total - The web UI at your Langfuse URL provides visual exploration of traces
Related Skills
ddnetters/invoking-codex-exec
development
VerifiedTrustedCommunity
Use when delegating a single coding task to `codex exec` ("hand off to codex", "run codex on this", "dispatch codex on this ticket", any one-shot invocation). Covers flags, sandbox traps, monitoring, and recovery. Not for multi-issue parallel batches — use codex-issue-waves for those.
SKILL.mdUpdated May 3, 2026
ddnetters/codex-task-waves
development
VerifiedTrustedCommunity
Use when the user says "have codex fix this" / "have codex implement this" / "let codex handle this" / "give this to codex" / "delegate this to codex" for a single task with context already in scope (a Jira ticket, GitHub issue, file diff, bug, or described change). Plans the work, splits it into reviewable waves, dispatches codex per wave with review and correction between waves before opening a PR. Not for multi-issue parallel batches (use codex-issue-waves) or one-shot codex runs without planning (use invoking-codex-exec).
SKILL.mdUpdated May 3, 2026
ddnetters/codex-issue-waves
development
VerifiedTrustedCommunity
Run a batch of GitHub issues through codex exec in isolated git worktrees as parallel autonomous PRs, then manage the review and correction waves until merge. Use when the user gives a list of issue numbers (≥ 2) and asks to "spawn codex" / "dispatch codex" / "have codex work on" / "manage the PRs" / "process feedback" / "get them merged" for those issues, or when the user asks for multi-issue parallel delegation to codex. Not for single-issue wave-driven delegation (use codex-task-waves), single-issue one-shot dispatch (use invoking-codex-exec), or implementation without delegation (use /pr or direct implementation).
SKILL.mdUpdated May 3, 2026
ddnetters/slite-knowledge-base
development
VerifiedTrustedCommunity
Slite knowledge base API — ask questions, search notes, retrieve content, manage users and groups, and audit knowledge health via the REST API
SKILL.mdUpdated Apr 25, 2026