agent: builder model: opus max_turns: 70 budget_usd: 14 —
for walks, so D13’s turn count reaches a for over a collectionFacts: Where things live, Traps already met, Commands
Score: S=3 (claim (b), the owner’s 100 % target: the counter reason holds 541 of the unproved sites under on, most of them at += 1 in a for x in xs), O=3 M (every user’s for x in xs { n += 1 } keeps its overflow check today), C=3 M (one fact in the checker; p6’s walk code already reads it). Area: prover.
.len())p6 (28acd94) built ADR-361 D13 in the bounds walk, but the walk learns a collection’s length only where the checker recorded it in facts.std_lengths / facts.sized_lengths (check_core_method.nika :916-921, .len() receivers only). check_core_stmt_for records the iterable the same way: when check_core_method_counted(over) (make it pub), insert id_of(iter) as i64 into std_lengths, and into sized_lengths where state.elements_take_space(over). A map or set walks one turn per entry, a list one per element. (for c in text over a String passes check and fails in rustc today, #1075; leave it to the bug lane.) Nothing else changes: bounding_length (bounds_walk.nika :1715) reads the fact by node_key(receiver).
target/fast/nikaia check --bounds tests/compiler/tests/prove_for_counts_its_turns.nika (copy it outside tests/compiler): line 11 every’s at += 1, line 20 some’s n += 1, line 30/33 same’s xs[at] and at += 1 are checked: a counter a loop changes, with no bound tied to the loop's turns; only line 44 (ranged) is proved. After this brief all four are proved at both settings (off and prove-through-loops:on); the soundness rows (52 unbounded start, 60 u8 n += 2, 71 reset, 80 inner-loop growth, 89 n * 2, 97 u8 over an unknown range) stay checked. If a soundness row turns proved, stop at once: that is a wrong proof.
scripts/where.nika, 2026-10-31)crates/nikaia-std/src/tools/check_core_stmt.nika :1558 check_core_stmt_for (record after let over = check_core_expr(...)).crates/nikaia-std/src/tools/check_core_method.nika :187 check_core_method_counted (to pub), :916-921 the .len() recording to mirror.crates/nikaia-std/src/tools/check_decls.nika :76 elements_take_space.bounds_walk.nika :1715 bounding_length, and p6’s bounding_turn_bounds. If the walk does not pick the fact up unchanged, the fix in bounds_walk.nika is allowed (say what in Body:)..nika (lower-std), commit its lowered/*.rs. None of these files is in docs/briefs/batch.txt or docs/briefs/bugs/batch.txt’s current briefs.prove_for_counts_its_turns.bounds and .loops.bounds re-blessed (nikaia test --project tests/compiler --bless prove_for_counts_its_turns or the way p5 built) and read through line by line against the list above. Add two rows to prove_for_counts_its_turns.nika (use std::collections): for (k, v) in m over m: collections::HashMap[String, i64] with n += 1 (proved after), and for c in text.chars() (text: String) with n += 1 (stays checked: a produced sequence has no length the checker records; probed, it runs and prints today). Both .bounds files changed accordingly.tests/compiler test named prove_* or bounds_* (nikaia test --project tests/compiler --both-settings), cargo test -p nikaia --test it -- prove bounds. A test whose .bounds rightly gains a proof is re-blessed and named in Body:.target/fast/nikaia lower-std --bounds > R and ... --optimization prove-through-loops:on > R2, target/fast/nikaia run scripts/proved.nika -- R / -- R2: both proved: lines and the counter reason’s count under Tests: and in Body: (28acd94: off 1,520/2,646 indexes, 733/1,620 operations; on 1,552/2,646, 740/1,620; counter 541 on). Part: #1053.Changelog: write one sentence (a prover change raises the version), not none.
The tests above pass; lower-std fixpoint clean; build, fmt, clippy, pre-push-check.sh; committed locally. Stop about 15 turns before max_turns, commit what is finished and report partial.
An edit is needed outside the files under Locations, their lowered twins and the tests; a soundness row turns proved; an error in another agent’s file.
Not yours, never stage: every file git status shows modified or untracked at your start (crates/nikaia-std/src/tools/lowered/project_members.rs is residue, #1060), and every docs/briefs/* file except your report.
docs/builder-facts.md first. develop in the main checkout; git status at start: other agents’ uncommitted files are not yours, never touch or stage them.git add <files> only (scripts/commit.nika -- REPORT does it); commit locally after each step and never push: the driver runs the complete suite and pushes (.claude/agents/builder.md, Cheap checks only; owner, 2026-10-31).cargo build --profile fast -p nikaia, lower-std and its fixpoint when a tools/*.nika changed, cargo fmt, cargo clippy --all-targets -- -D warnings, scripts/pre-push-check.sh, the tests the brief names and the ones your change touches. No gate.nika.CHANGELOG.md, badges; no new NK code. New tests in Nikaia only; never the full suite. No foreground sleep, no polling; scripts in files.std or the toolchain lacks stops the work: no code around it unless an ADR or Part I-III refuses it (name it). Else Result: blocked, Found: gap + probe, Needs: architect decision (CLAUDE.md, A missing form stops the work).NIKAIA_CACHE_LIMIT=2G; at most two clones with target/ in the machine; delete your own clone’s target/ and target/release/nikaia-scratch at the end; report GB freed.Result: partial with what you ruled out, the probe, and the suspected file and function (.claude/agents/builder.md).target/fast/nikaia run scripts/commit.nika -- REPORT, which writes Pushed: local <sha> into it. A report without a Pushed: line, or with a placeholder left in (TC, DISK), is not done and cuts the batch (k3a1 2026-10-29: Result: done, nothing committed)./home/user/Nikaia/docs/briefs/prover/p7-1053-for-collection-length.md.report.md)Fields of docs/architect.md, Briefs and reports: Result: done|noop|partial|blocked (the bare word alone on that line: Result: done, never a summary after it, which cuts the batch, b869a 2026-10-27; Owner: is a question for the owner or none, never a role), Files, Commit, Body (optional, one paragraph for the commit message), Fixes, Pushed, Tests, Gate (green|red), Deviation, Found, Needs, Changelog, Owner, Disk freed, and for a move Rs2nika: (the kept N of M lines of rs2nika --score, then the three costliest hand edits; none for a task that moves no Rust, none (redesign) for a brief with Shape: redesign and no Convert: line). none where nothing, and then the bare word: Deviation: none (a note) cuts the batch (batch.nika compares exactly); a note goes into the commit message. Found: is only for a defect outside your change (it cuts the batch); a process event such as another session resetting or rewriting your files is no Found:, it goes under Needs: (m3a 2026-10-28); a converter draft that came out wrong is no Found:, it is one of the costliest edits under Rs2nika:, which the converter lane reads (e12-4b 2026-10-27); how you solved your own step goes into the commit message. Deviation: is only a step of the brief built otherwise than written or not built (a choice the brief left to you, such as keep what X needs and say so, is no deviation: it goes into the commit message; nor is building two steps in one commit when every step is built, e12-3a 2026-10-27, nor a step another commit on develop already built, shown by your test failing with that commit’s change reverted, b889 2026-10-27: name the commit in Body:, nor a test’s expected .stdout/.stderr taken from what the program really prints where the brief’s sketch of it was short or wrong, b934 2026-10-29: say so in Body:, nor a lowering that follows the ADR governing it where the brief’s expected lowering contradicts that ADR, b933 2026-10-29: name the ADR in Body:, nor a lowering other than the brief’s where rustc cannot take the brief’s, b1029 2026-10-31: say why in Body:, nor re-keying an allow-list entry (KNOWN) whose hash changed for the same program and the same reason, b-fixforward-sweep2 2026-10-28: say so in Body:, nor an existing test’s expected .stdout/.stderr updated because your change rightly changes the message it prints, b1012b 2026-10-31: name the test in Body:); how you verified (e.g. a test not run against the unfixed compiler) goes under Tests:. A noop says why under Tests: (what was probed), not under Deviation:. Final answer, one line: done <sha>, report <path> (or BLOCKED: ... / PUSH REJECTED ...).
Attribution: Co-Authored-By: Claude Opus 5.5 noreply@anthropic.com Claude-Session: https://claude.ai/code/session_01UVxJDtwVhc6jMtEYAyvwLU