Langfuse

Quadrant distribution

Jev `choice` — not a hard 0.5 cut. Confidence 0.77.

• Directed3.0%
• Forming2.0%
• Anchored12.0%
• Operational83.0%

Evidence ledger

Recency half-life 180 days. Weight = 2^(-age/180).

1. release · published 2026-08-17 · w=0.861

   Langfuse v4 is live

   Langfuse v4 launched on Langfuse Cloud and as GA for self-hosted deployments, claiming millisecond table loads and at least 10× faster long-range dashboards. Cloud becomes v4-only on 16 November 2026; v3 self-host security patches run through January 2027.

2. announcement · published 2026-05-31 · w=0.637

   Langfuse May 2026 update / launch week

   Langfuse’s May launch week shipped MCP, experiments in CI/CD, and an Agent Skill that coding agents can use to instrument apps and set up evaluators.

3. release · published 2026-09-03 · w=0.919

   Langfuse Assistant

   Langfuse shipped an Assistant for analyzing thousands of observations, with accompanying agent-skill and CLI guidance.

Reproducibility

resolved model: jev-1.13.0

requested model: jev-latest

request id: req_01a0d5e180787814b7aa9344ae23dfd5

timestamp: 2026-09-25T00:05:17.859Z

request hash: d4648692c1a52e3c34f5d719dc8a5c6d0ea10e540ca02778df4a1c38d1e8cd7e

{
  "model": "jev-latest",
  "state": {
    "goal": "Score this entity on the Jev Quadrant rubric using only the supplied evidence.",
    "framework": "jev-quadrant-v1",
    "topic": {
      "id": "agent-observability",
      "title": "Agent observability and guardrails",
      "x_axis": "Proven Execution",
      "y_axis": "Validated Direction"
    },
    "entity": {
      "id": "langfuse",
      "name": "Langfuse",
      "website": "https://langfuse.com",
      "description": "Open-source LLM and agent observability with cloud and self-host options."
    },
    "evidence": [
      {
        "id": "langfuse-v4",
        "kind": "release",
        "url": "https://langfuse.com/changelog/2026-08-17-langfuse-v4",
        "date": "2026-08-17",
        "date_kind": "published",
        "recency_weight": 0.8606,
        "summary": "Langfuse v4 launched on Langfuse Cloud and as GA for self-hosted deployments, claiming millisecond table loads and at least 10× faster long-range dashboards. Cloud becomes v4-only on 16 November 2026; v3 self-host security patches run through January 2027.",
        "title": "Langfuse v4 is live"
      },
      {
        "id": "langfuse-may",
        "kind": "announcement",
        "url": "https://langfuse.com/blog/2026-05-31-langfuse-may-update",
        "date": "2026-05-31",
        "date_kind": "published",
        "recency_weight": 0.6373,
        "summary": "Langfuse’s May launch week shipped MCP, experiments in CI/CD, and an Agent Skill that coding agents can use to instrument apps and set up evaluators.",
        "title": "Langfuse May 2026 update / launch week"
      },
      {
        "id": "langfuse-assistant",
        "kind": "release",
        "url": "https://langfuse.com/changelog/2026-09-03-langfuse-assistant",
        "date": "2026-09-03",
        "date_kind": "published",
        "recency_weight": 0.9188,
        "summary": "Langfuse shipped an Assistant for analyzing thousands of observations, with accompanying agent-skill and CLI guidance.",
        "title": "Langfuse Assistant"
      }
    ],
    "claims": [],
    "independent_checks": [],
    "recency": {
      "half_life_days": 180,
      "as_of": "2026-09-25",
      "mass": 2.4166
    }
  },
  "questions": {
    "exec_shipped": {
      "type": "noul",
      "instructions": "Use only the supplied state. Do not use prior knowledge that is not represented as evidence items. If evidence is thin, return a probability near 0.5 with the understanding that uncertainty is handled separately. Has this entity shipped a generally available product used by third parties?",
      "criteria": {
        "true": "Independent public evidence shows a generally available product used by third parties.",
        "false": "The product is announced, preview-only, or evidenced only by unsourced vendor marketing with no third-party use."
      }
    },
    "exec_adoption": {
      "type": "noul",
      "instructions": "Use only the supplied state. Do not use prior knowledge that is not represented as evidence items. If evidence is thin, return a probability near 0.5 with the understanding that uncertainty is handled separately. Is there credible adoption evidence?",
      "criteria": {
        "true": "Credible adoption evidence exists: named customers, published user or download counts, case studies, or equivalent.",
        "false": "Adoption claims are absent, purely anecdotal, or unsourced."
      }
    },
    "exec_reliability": {
      "type": "noul",
      "instructions": "Use only the supplied state. Do not use prior knowledge that is not represented as evidence items. If evidence is thin, return a probability near 0.5 with the understanding that uncertainty is handled separately. Is there evidence of reliability, quality, security/compliance, or operational maturity?",
      "criteria": {
        "true": "Evidence of reliability, quality, security/compliance, or operational maturity (uptime, incidents handled, certifications, long-running open-source project).",
        "false": "No reliability or quality evidence is present."
      }
    },
    "exec_cadence": {
      "type": "noul",
      "instructions": "Use only the supplied state. Do not use prior knowledge that is not represented as evidence items. If evidence is thin, return a probability near 0.5 with the understanding that uncertainty is handled separately. Is there evidence of continued delivery after launch?",
      "criteria": {
        "true": "Evidence of continued delivery after launch (dated releases, changelog, subsequent features).",
        "false": "Delivery appears one-shot or stalled."
      }
    },
    "dir_strategy": {
      "type": "noul",
      "instructions": "Use only the supplied state. Do not use prior knowledge that is not represented as evidence items. If evidence is thin, return a probability near 0.5 with the understanding that uncertainty is handled separately. Is there a specific, consistent, dated public strategy or roadmap?",
      "criteria": {
        "true": "A public strategy or roadmap is specific, consistent, and dated.",
        "false": "Direction is vague, contradictory, or only implied."
      }
    },
    "dir_backed": {
      "type": "noul",
      "instructions": "Use only the supplied state. Do not use prior knowledge that is not represented as evidence items. If evidence is thin, return a probability near 0.5 with the understanding that uncertainty is handled separately. Are strategy or roadmap claims backed by shipped artifacts in the evidence pack?",
      "criteria": {
        "true": "Roadmap or strategy claims are backed by shipped artifacts in the evidence pack.",
        "false": "Direction is promised without corresponding delivery evidence."
      }
    },
    "dir_distinct": {
      "type": "noul",
      "instructions": "Use only the supplied state. Do not use prior knowledge that is not represented as evidence items. If evidence is thin, return a probability near 0.5 with the understanding that uncertainty is handled separately. Is the evidenced direction distinct from generic category copy?",
      "criteria": {
        "true": "The evidenced direction is distinct from generic category copy.",
        "false": "Positioning is interchangeable with peers."
      }
    },
    "dir_invested": {
      "type": "noul",
      "instructions": "Use only the supplied state. Do not use prior knowledge that is not represented as evidence items. If evidence is thin, return a probability near 0.5 with the understanding that uncertainty is handled separately. Is there evidence of sustained investment in this product?",
      "criteria": {
        "true": "Evidence of sustained investment (funding used for the product, research, open-source velocity, or platform expansion).",
        "false": "No evidence of continued investment."
      }
    },
    "quadrant": {
      "type": "choice",
      "instructions": "Use only the supplied state. Do not use prior knowledge that is not represented as evidence items. If evidence is thin, return a probability near 0.5 with the understanding that uncertainty is handled separately. Assign the entity to one Jev Quadrant cell. Do not use a hard 0.5 cut. Weigh the full evidence pack.",
      "criteria": {
        "ANCHORED": "Both delivery (proven execution) and evidenced direction (validated direction) are strong.",
        "DIRECTED": "Validated direction is better evidenced than proven execution.",
        "OPERATIONAL": "Proven execution is better evidenced than validated direction.",
        "FORMING": "Both axes are thin, early, or contradicted."
      }
    }
  }
}

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