feat(skills): interviewing - one source for the brief's question round (order 7e)

/trekbrief Phase 3 carried the interview form inline. It now asks for the
new skill voyage:interviewing by name (allowed-tools gains Skill) and keeps
only its own contract: the size class and budget, the three fixed questions
(framing first, class, storage), where each answer lands in the brief, and
the answers that decide nothing. Step 3a and the form points of Step 3c move
into the skill with their credits (Pocock, Osmani, Spec Kit; licences and
line ranges checked at the pinned commits).

Red baseline first (3 helper interviews against a fixed answer sheet,
Opus 5.5): 10-11 questions in round 1 (3 of 3), 15 of 31 without a
recommendation, a hollow answer written in as a decision (2 of 3), unasked
scope as a requirement (2 of 3). With the skill: 4, 0 of 12, 0 of 3, 0 of 3.
Fact questions and stopping did not fail without it.

Also: pointers to voyage:writing-criteria (S3) where criteria are asked and
written, both review skill names (S3 + S4) in the brief-reviewer prompt; the
intent pins that read moved text now read the skill, same assertions; the
Phase 7 line_ref moves with the shorter Phase 3; 7 eval cases (3/2/2).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

evals/skill-interviewing-effect-hollow/graders/hollow-kept-apart.md

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+---
+type: llm
+focus: last_message
+---
+
+Answers 3, 4 and 5 decided nothing ("Whatever you think is best", "Sounds good"). PASS only if whatever the reply writes for points 3, 4 and 5 is marked as an assumption or as not confirmed by the person (or is left open or deferred), and is visibly kept apart from what the person decided in answers 1, 2 and 6. FAIL if any of points 3, 4 or 5 is presented as the person's decision, or listed among the person's explicit choices, limits or exclusions without such a mark.

evals/skill-interviewing-effect-hollow/graders/no-unasked-scope.md

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+---
+type: llm
+focus: last_message
+---
+
+PASS only if every requirement in the reply traces to one of the six questions and answers. A new command, data field, rule or behaviour that no question raised may appear only as a marked assumption, a deferred item or a question back to the person. FAIL if the reply adds such a thing as a plain requirement.

evals/skill-interviewing-effect-hollow/prompt.md

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+---
+description: "Effect case for interviewing (two arms: with and without the plugin). The write-up after a round where several answers decided nothing. Without the skill, 2 of 3 of Voyage's baseline helpers wrote such answers into the requirements as the person's own decisions (one listed them under \"operator's explicit no\"), and 2 of 3 wrote in scope nobody asked for; with it (measured in session 17.10 in the full relayed interview, not in this one-prompt form), 0 of 3 did either. The operator grants no tools beyond Skill, and sets the judge model explicitly (never Haiku)."
+expected_outcome: "The requirements keep three things apart: what the person decided, what was assumed for an answer that decided nothing (each marked not confirmed), and what is deferred; nothing the person never asked for appears as a requirement."
+tags: [skill-effect, skill=interviewing, from=baseline-ivw-hollow-answer]
+runs: 3
+max_turns: 6
+timeout_seconds: 300
+allowed_tools: [Skill]
+---
+
+You are interviewing me about a feature for our garden club's seed-library app: members forget to bring seeds back after harvest. You already asked one round of questions, and here are my answers. Write the requirements now, as a list I can approve.
+
+Your questions and my answers:
+
+1. Q: How should reminders reach members? (Recommended: the printed meeting sheet the app already writes to.) A: Yes, go with your suggestion.
+2. Q: When should reminders go out? (Recommended: once a week for every loan overdue or due within two weeks.) A: Once a week, overdue or due within two weeks. Never the same reminder twice in one week.
+3. Q: Should a member who is still late keep getting reminders forever, or should they stop after a while? A: Whatever you think is best.
+4. Q: Should due dates depend on the crop, since kale only sets seed in its second year? A: Whatever you think is best.
+5. Q: What should happen when a member's harvest failed? A: Sounds good.
+6. Q: Any consequence for late members, such as blocking new loans? A: No fines and no blocking anyone. Just a friendly nudge.

evals/skill-interviewing-effect-round/case.yaml

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+schema_version: "1.1"
+name: skill-interviewing-effect-round
+context:
+  scaffold_script: scaffold.sh

evals/skill-interviewing-effect-round/graders/four-at-most-recommended-first.md

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+---
+type: llm
+focus: last_message
+---
+
+PASS only if the reply asks the person at most four questions, and every question gives a recommended answer before or as its first option (marked "Recommended", "Suggested", "I recommend" or similar). A question that bundles two or more separate decisions counts as that many questions. FAIL if the reply asks five or more questions, or if any question has no recommended answer.

evals/skill-interviewing-effect-round/graders/rest-written-down.md

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+---
+type: llm
+focus: last_message
+---
+
+PASS only if the reply writes down what it did not ask: assumptions it made (marked as assumed, not decided by the person) or a deferred list of open points, or says plainly that nothing else is open. FAIL if the reply leaves open points neither asked nor written down, or presents its own assumptions as the person's decisions.

evals/skill-interviewing-effect-round/prompt.md

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+---
+description: "Effect case for interviewing (two arms: with and without the plugin). The first round where Voyage's baseline helpers failed without the skill: 3 of 3 sent 10 or 11 questions in one block, and 15 of 31 questions carried no recommended answer; with it (measured in session 17.10), 3 of 3 sent 4, and 0 of 12 lacked one. None asked a fact the project could answer, so that is not graded here. The operator grants Read, Glob and Grep, and sets the judge model explicitly (never Haiku)."
+expected_outcome: "The reply asks at most four questions, each with a recommended answer first, none about something the project files answer; what it does not ask is written down as an assumption or a deferred item."
+tags: [skill-effect, skill=interviewing, from=baseline-ivw-round-size]
+runs: 3
+max_turns: 20
+timeout_seconds: 600
+allowed_tools: [Read, Glob, Grep, Skill]
+---
+
+I run a small seed library for my garden club. The app is the project in the current directory.
+
+Members keep forgetting to bring seeds back after harvest, and I want the app to do something about that. Before anyone writes code, interview me so we get the requirements right.
+
+How this works: you cannot reach me directly. Put whatever you want to ask me in your reply, and I will send my answers back to you in a message. Do not change any files in the project.

evals/skill-interviewing-effect-round/scaffold.sh

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+#!/bin/bash
+# Seeds the empty run workspace with a small seed-library app (Node, node --test),
+# made up from scratch. Self-contained on purpose: the run cannot read the eval
+# directory, and the fixture is written inline, with no path outside the
+# workspace and no git. The same project the red baseline ran against.
+set -eu
+mkdir -p src tests data
+cat > package.json <<'J'
+{ "name": "seedswap", "version": "0.4.1", "type": "module", "private": true,
+  "engines": { "node": ">=20" },
+  "scripts": { "test": "node --test", "start": "node src/cli.mjs" } }
+J
+cat > README.md <<'J'
+# seedswap
+
+A seed library for a garden club. Members borrow seed packets in spring and
+bring back seeds from their own harvest in autumn. One volunteer runs this
+command-line tool on the club laptop.
+
+    node src/cli.mjs borrow <member> <variety>
+    node src/cli.mjs return <member> <variety>
+    node src/cli.mjs list
+
+Data lives in `data/*.json`. Messages to members go to `data/outbox.txt`,
+which the volunteer prints and hands out at the monthly meeting.
+J
+cat > src/store.mjs <<'J'
+import { readFileSync, writeFileSync } from 'node:fs';
+const path = (name) => new URL(`../data/${name}.json`, import.meta.url);
+export const load = (name) => JSON.parse(readFileSync(path(name), 'utf8'));
+export const save = (name, value) => writeFileSync(path(name), JSON.stringify(value, null, 2) + '\n');
+J
+cat > src/members.mjs <<'J'
+import { load } from './store.mjs';
+// A member: { id, name, joined }. No email or phone is stored.
+export const members = () => load('members');
+export const byId = (id) => members().find((m) => m.id === id);
+J
+cat > src/loans.mjs <<'J'
+import { load, save } from './store.mjs';
+// A loan: { member, variety, borrowed: 'YYYY-MM-DD', due: 'YYYY-MM-DD', returned: null | 'YYYY-MM-DD' }.
+// `due` is set to 15 October of the borrowing year (end of harvest).
+export function borrow(member, variety, today) {
+  const loans = load('loans');
+  const due = `${today.slice(0, 4)}-10-15`;
+  loans.push({ member, variety, borrowed: today, due, returned: null });
+  save('loans', loans);
+}
+export function giveBack(member, variety, today) {
+  const loans = load('loans');
+  const open = loans.find((l) => l.member === member && l.variety === variety && !l.returned);
+  if (!open) throw new Error(`no open loan of ${variety} for ${member}`);
+  open.returned = today;
+  save('loans', loans);
+}
+export const openLoans = () => load('loans').filter((l) => !l.returned);
+J
+cat > src/notify.mjs <<'J'
+import { appendFileSync } from 'node:fs';
+// Appends one message for a member to data/outbox.txt (printed at meetings).
+export function notify(member, text, today) {
+  appendFileSync(new URL('../data/outbox.txt', import.meta.url), `${today}\t${member.name}\t${text}\n`);
+}
+J
+cat > src/cli.mjs <<'J'
+import { borrow, giveBack, openLoans } from './loans.mjs';
+const [cmd, member, variety] = process.argv.slice(2);
+const today = new Date().toISOString().slice(0, 10);
+if (cmd === 'borrow') borrow(member, variety, today);
+else if (cmd === 'return') giveBack(member, variety, today);
+else if (cmd === 'list') for (const l of openLoans()) console.log(`${l.member}\t${l.variety}\tdue ${l.due}`);
+else { console.error('usage: borrow|return|list'); process.exit(2); }
+J
+cat > tests/loans.test.mjs <<'J'
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+test('loans module loads', async () => {
+  const m = await import('../src/loans.mjs');
+  assert.equal(typeof m.borrow, 'function');
+});
+J
+cat > data/members.json <<'J'
+[ { "id": "m1", "name": "Ada", "joined": "2023-03-02" },
+  { "id": "m2", "name": "Bo", "joined": "2024-04-11" },
+  { "id": "m3", "name": "Cy", "joined": "2025-02-20" } ]
+J
+cat > data/loans.json <<'J'
+[ { "member": "m1", "variety": "tomato-moneymaker", "borrowed": "2026-04-02", "due": "2026-10-15", "returned": null },
+  { "member": "m2", "variety": "bean-borlotti", "borrowed": "2026-04-09", "due": "2026-10-15", "returned": "2026-09-30" },
+  { "member": "m3", "variety": "kale-nero", "borrowed": "2025-04-20", "due": "2025-10-15", "returned": null } ]
+J
+: > data/outbox.txt

evals/skill-interviewing-fires-1/graders/skill-fired.md

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+---
+type: tool_used
+tool: Skill
+input_match: '"skill"\s*:\s*"(?:voyage:)?interviewing"'
+---

evals/skill-interviewing-fires-1/prompt.md

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+---
+description: "Routing case: the interviewing skill should fire on this request (the reserve path outside the pipeline)."
+expected_outcome: "Claude calls the Skill tool for voyage:interviewing at least once."
+tags: [skill-trigger, skill=interviewing, from=baseline-ivw-round-size]
+runs: 3
+max_turns: 4
+allowed_tools: [Read, Glob, Grep, Skill]
+---
+
+Before anyone writes code, interview me about this feature so we get the requirements right.

evals/skill-interviewing-fires-2/graders/skill-fired.md

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+---
+type: tool_used
+tool: Skill
+input_match: '"skill"\s*:\s*"(?:voyage:)?interviewing"'
+---

evals/skill-interviewing-fires-2/prompt.md

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+---
+description: "Routing case: the interviewing skill should fire on this request (the reserve path outside the pipeline)."
+expected_outcome: "Claude calls the Skill tool for voyage:interviewing at least once."
+tags: [skill-trigger, skill=interviewing, from=skillsanalyse-4.7]
+runs: 3
+max_turns: 4
+allowed_tools: [Read, Glob, Grep, Skill]
+---
+
+Grill me on this idea: ask me the questions you need answered, each with your recommended answer, and stop when you can predict what I will say.

evals/skill-interviewing-fires-3/graders/skill-fired.md

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+---
+type: tool_used
+tool: Skill
+input_match: '"skill"\s*:\s*"(?:voyage:)?interviewing"'
+---

evals/skill-interviewing-fires-3/prompt.md

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+---
+description: "Routing case: the interviewing skill should fire on this request (the reserve path outside the pipeline)."
+expected_outcome: "Claude calls the Skill tool for voyage:interviewing at least once."
+tags: [skill-trigger, skill=interviewing, from=baseline-ivw-hollow-answer]
+runs: 3
+max_turns: 4
+allowed_tools: [Read, Glob, Grep, Skill]
+---
+
+What I want from the reminder feature is still vague. Draw the requirements out of me with questions, and keep apart what I decided from what you assumed.

evals/skill-interviewing-quiet-1/graders/skill-quiet.md

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+---
+type: tool_used
+tool: Skill
+input_match: '"skill"\s*:\s*"(?:voyage:)?interviewing"'
+min: 0
+max: 0
+arm: both
+---

evals/skill-interviewing-quiet-1/prompt.md

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+---
+description: "Routing case: the interviewing skill must stay quiet here; /trekbrief owns this request (it runs the interview itself and asks for the skill by name)."
+expected_outcome: "Claude never calls the Skill tool for voyage:interviewing."
+tags: [skill-no-trigger, skill=interviewing, owner=trekbrief, from=order-7e-no-collision]
+runs: 3
+max_turns: 4
+allowed_tools: [Read, Glob, Grep, Skill]
+---
+
+Produce a task brief with an explicit research plan for adding a dark-mode setting, ready to feed research and planning.

evals/skill-interviewing-quiet-2/graders/skill-quiet.md

@@ -0,0 +1,8 @@
+---
+type: tool_used
+tool: Skill
+input_match: '"skill"\s*:\s*"(?:voyage:)?interviewing"'
+min: 0
+max: 0
+arm: both
+---

evals/skill-interviewing-quiet-2/prompt.md

@@ -0,0 +1,10 @@
+---
+description: "Routing case: the interviewing skill must stay quiet here; brief-reviewer owns this request (reviewing a finished brief is not interviewing anyone)."
+expected_outcome: "Claude never calls the Skill tool for voyage:interviewing."
+tags: [skill-no-trigger, skill=interviewing, owner=brief-reviewer, from=skillsanalyse-4.7]
+runs: 3
+max_turns: 4
+allowed_tools: [Read, Glob, Grep, Skill]
+---
+
+Review this task brief for completeness, consistency, testability and scope clarity before exploration begins.