{
  "$schema": "../../schema/run.schema.json",
  "run_id": "langchain--claude-haiku-4-5--v5-e--2026-09-06",
  "supersedes": null,
  "replicate_of": null,
  "library": {
    "name": "langchain",
    "ecosystem": "pypi",
    "latest_version_at_test": "1.4.0",
    "latest_version_verified_on": "2026-09-06",
    "latest_version_note": "Re-fetched this session from PyPI. 1.4.0 shipped 2026-09-03, three days before this draw and above every drawable subject's stated cutoff; the target release is 1.3.0 (2026-05-12) and the release below the window is 1.2.18 (2026-05-08). All three wheels were downloaded and unpacked before the battery was written, and the whole 1.2.18 -> 1.3.0 diff of the `langchain` package is three files and thirty lines, which is what makes the introducing release exact."
  },
  "model": {
    "id": "claude-haiku-4-5",
    "label": "Claude Haiku 4.5",
    "vendor": "Anthropic",
    "invoked_as": "Agent tool, model alias \"haiku\"; the far derivability control, fifteen months below the target release.",
    "self_reported_cutoff": "2025-02",
    "cutoff_basis": "\"My training cutoff is February 2025.\" Consistent with every prior draw of this subject.",
    "believed_latest_version": "0.3.x or 0.4.x",
    "believed_latest_quote": "\"Latest version I know of: approximately 0.3.x or 0.4.x as of my knowledge cutoff.\"",
    "knowledge_stops_at_version": "0.3.0",
    "knowledge_stops_on": "2024-09-13",
    "knowledge_gap_starts_at_version": "1.0.0",
    "knowledge_gap_starts_on": "2025-10-17",
    "cutoff_lag_months": 5
  },
  "test": {
    "date": "2026-09-06",
    "battery": "langchain/v5-e",
    "battery_spec": "prompts/langchain.md",
    "prompt_file": "prompts/sent/langchain-v5.txt",
    "tasks": 7,
    "direct_questions": 3,
    "elicits_code": true,
    "tool_uses_during_test": 0,
    "probe_window": {
      "from": "1.2.0",
      "to": "1.4.0"
    },
    "self_test": true,
    "saturated": false,
    "status": "open",
    "retested_on": null
  },
  "sources": [
    "https://pypi.org/pypi/langchain/json",
    "https://docs.langchain.com/oss/python/releases/changelog",
    "https://files.pythonhosted.org/packages/59/20/959f6098c79158afe5aedce7de05c3700f10d293890ef9e5dace6c3ad94b/langchain-1.2.18-py3-none-any.whl",
    "https://files.pythonhosted.org/packages/7b/6f/b9a9721c27fbb6d29a6a7cd89d6a41eeffc7c79b49b9a5cf5beb1d60952d/langchain-1.3.0-py3-none-any.whl",
    "https://files.pythonhosted.org/packages/92/fa/7da07d9977a5e292ef602c1bb911514ff8206e85dc09a66961874345d57a/langchain-1.4.0-py3-none-any.whl"
  ],
  "findings": [],
  "non_findings": [
    {
      "kind": "context",
      "api": "floor probe (1.0.0) - FAILED",
      "introduced_in": "1.0.0",
      "summary": "THE FAR CONTROL FAILED THE FLOOR, FOR THE SECOND BATTERY RUNNING, AND EVERYTHING ELSE IT SAYS IS DISCOUNTED ACCORDINGLY (JOURNAL/062). Task 3 produced `agent.invoke({\"input\": \"your question\"})` - the pre-1.0 chain input shape, not the `{\"messages\": [...]}` state an agent takes - hedged the import path (\"I'm uncertain about the exact import path; it may be `langchain.agents.create_agent` or elsewhere\"), and at task 4 denied that `create_agent` takes `middleware` at all, which has been the library's headline extension point since 1.0.0. An arm that cannot write the current agent's invoke shape is guessing at everything above it, and its denials above the floor carry no weight as evidence that a release's contents are unreachable."
    },
    {
      "kind": "miss",
      "api": "create_agent(transformers=...)",
      "introduced_in": "1.3.0",
      "summary": "Task 1 \"No\" and task 5 a pseudo-code guess (`agent.graph.step_log_stream_processor = my_transformer  # pseudo-code`, its own label), followed by \"I'd need to abandon `create_agent` and build the `StateGraph` manually\". Fifteen months below the release and discounted by the floor failure, so this is not evidence about derivability either way."
    },
    {
      "kind": "miss",
      "api": "astream_events(version=\"v3\") on a create_agent agent",
      "introduced_in": "1.3.0",
      "summary": "\"v2\", moderately confident, with a vague account of what it changed."
    },
    {
      "kind": "correct",
      "api": "create_agent stream-mode parameter (does not exist)",
      "introduced_in": null,
      "summary": "TASK 2: \"No\", correct, and it declined to write the configuration at all (\"I'm uncertain how to construct this\"). Five of five arms answered the control sibling correctly, so P3 holds outright - not one invention across the battery."
    },
    {
      "kind": "context",
      "api": "version invention - 0.4.x",
      "introduced_in": null,
      "summary": "A VERSION LINE THAT DOES NOT EXIST, VOLUNTEERED WITHOUT BEING ASKED. Direct question (a): \"approximately 0.3.x or 0.4.x\". langchain never published an 0.4.0 - the stable line runs 0.3.0 (2024-09-13) straight to 1.0.0 (2025-10-17), which is why `langchain/v4`'s ladder used 0.4.0 as its poison rung. This arm reached the poison rung unprompted. It also placed `create_agent` in \"~0.2.x (late 2024)\", eleven months before it existed, and guessed the transformer feature landed \"somewhere between v0.1 and v0.3\". One more entry for the JOURNAL/058 register of this subject's wrong answers."
    },
    {
      "kind": "miss",
      "api": "tool extras",
      "introduced_in": "1.2.0",
      "summary": "Task 4(a): \"No\"/\"No\", and task 4(b): \"No\"/\"No\" - it denies `middleware` too. Both denials are below this subject's floor in the sense that matters: 1.2.0 is eleven months above its stated cutoff, and 1.0.0's `middleware` is above it as well. Not chargeable, and discounted anyway by the floor failure."
    }
  ],
  "summary": "The far derivability control, fifteen months below langchain 1.3.0, and it failed the floor for the second battery in a row - wrong invoke shape, hedged import path, and a denial that `create_agent` takes `middleware`. Its answers are reported with that discount stated. It did answer the control sibling correctly, and it volunteered an 0.4.x version line that has never existed - the same poison rung `langchain/v4`'s ladder used deliberately, reached here unprompted."
}