Rendered from docs/probe-runs/additive-screening-of-2026-10-18-scenario-13-the-tombstone-probe.md in the Headwater corpus. Every document on this half of the site is typed by the taxonomy the descriptor names: corpus.json.

Additive screening of 2026-10-18, scenario 13, the tombstone probe

Run identity

model: claude-sonnet-5
served_version: claude-sonnet-5
tree: sha256:7d84079327a6496ad99d1047ec2c9d0f82a810c3765b0ae22a4ae3ea97be60e8
lock: sha256:1fb804541b7441a6588f57cc93c893118896dbf705119c83b1f9f77072386124
selection: sha256:d4a51542343398c4c62fd22e5b7e4efd1a2f39ff54e81fed513de756e487f98e
read_set: sha256:f2bed904e8aa89a1c71328e44e2d90ffeadc9aacd7a1c1e1237a8158ee5b8923
seed: 0
harness: 0.6.0
tier: additive
arm: scenario-13
at: 2026-10-18
cost_cents: 327

This line is one of the screening round of the additive campaign that #1775 asked for. tools/probe/campaign.sh recorded it as line 15 of the plan of the batch, a plan that draws its 15 lines from tools/probe/additive-screening.spec. It is the scenario-13 arm of the additive tier over 1 probe of the tuning set, at 18 repetitions per probe, on claude-sonnet-5 under Claude Code 2.1.288 with a cap of 80 turns for each session.

One tree, one pin, one attempt. Every session ran in a fresh copy of a git archive of the pinned tree, and the engine of that tree. The pin was 2d212a26 for the whole batch, and the batch did not restart. The tree digest in the identity above is the digest the assembly recorded.

What the recorder counted. The line holds 18 sessions and cost 327 cents: the intent hook live in 18, 0 stopped at the turn cap, 0 stopped at the session budget, 0 paths outside the workspace named, 0 sessions uncounted, 0 web-tool calls. A session the recorder could not count adds nothing to either count, so each count is a floor.

The contract of this batch. The sessions ran under the recorder contract of spec 15: a bwrap sandbox with no network of its own, a configuration directory that holds a copy of the credentials and nothing else, the permission mode dontAsk, and WebSearch and WebFetch denied. The round approved $700 over every attempt, and the driver ran with a cap of 70000 cents and a session budget of 300 cents.

Where the raw recordings are. The raw session logs are outside git, under /mnt/build/hw-1775/screening/a/sessions/L15-*/raw.jsonl on the host that ran the batch. Nobody deletes them until the report of #1779 is published.

Where the figures are. The rates, the intervals and the comparisons of this line are in the generated result that reads this transcript, and this document states none of them.

Events

- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r1"
  calls:
    - tool: "Grep"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r1/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r1/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r1/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r10"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r10/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r10/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r11"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r11/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r11/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r12"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r12/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r12/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r12/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r13"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r13/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r13/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r14"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Skill"
      argument: "{\"skill\":\"headwater-orient\",\"args\":\"paragraph limit counts sentences under the language rule and never words\"}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r14/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r14/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r15"
  calls:
    - tool: "Bash"
      argument: "{\"command\":\"grep -n \\\"69\\\" -A 20 \\\"/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r15/docs/spec/09-open-questions.md\\\" | head -60\"}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r15/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r15/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r16"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r16/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Grep"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r16/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Grep"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r16/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r16/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r17"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r17/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r17/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r18"
  calls:
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r18/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r2"
  calls:
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r2/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r2/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r3"
  calls:
    - tool: "Skill"
      argument: "{\"skill\":\"headwater-orient\",\"args\":\"paragraph limit sentence count language rule open question 69\"}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r3/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r3/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r4"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r4/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r4/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r4/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r5"
  calls:
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r5/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r5/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r6"
  calls:
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r6/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r6/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r7"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r7/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r7/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r7/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r8"
  calls:
    - tool: "EnterWorktree"
      argument: "{}"
      result: ""
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r8/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r8/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r8/docs/decisions/0087-no-paragraph-limit-joins-the-language-rule-because-most-paragraphs-past-six-sentences-hold-one-topic.md"
      result: "sha256:fb83eb7fd0c0c778d8743eea38fbf729bc0b675ee37b82099ad43a0501ac03fd"
  produced: []
  answer: null
- probe: "HW-PROBE-an-agent-reaches-the-adjudication-when-the-decision-a-tombstone-links-is-superseded"
  session: "L15-additive-scenario-13-p1-r9"
  calls:
    - tool: "Grep"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r9/docs/spec/09-open-questions.md"
      result: "sha256:e0eb42b40e1ebf1364562b3e8a3b6f3f6c1f44cc5f81c2c951f1f07d845499f6"
    - tool: "Read"
      argument: "/mnt/build/hw-1775/screening/a/ws/L15-additive-scenario-13-p1-r9/docs/decisions/0069-a-paragraph-limit-counts-sentences-under-the-language-rule-and-never-words.md"
      result: "sha256:3accae5c8185e53e67b62ca6e107fe6cba75ca820626b8d914350b7487921c1c"
  produced: []
  answer: null