update skills

stage0/.claude/skills/port-astgen/SKILL.md

@@ -7,31 +7,60 @@ disable-model-invocation: true
 
 # Port AstGen — Orchestrator
 
-You manage the iterative porting loop. For each iteration you enable a
-skipped test, dispatch a worker agent, then verify and commit.
+You manage the iterative porting loop. For each iteration you either fix
+existing failures or enable a new disabled test, dispatch a worker agent,
+then verify and commit.
 
 **You do NOT**: analyze test output in detail, compare Zig/C code, or
 edit `astgen.c`. The worker handles all of that.
 
-## Loop
+## Phase 0: Check for leftovers
 
-Repeat until no `SkipZigTest` lines remain in `astgen_test.zig`.
+Before enabling anything new, run the existing tests:
 
-### Step 1: Find the first skipped test
+```sh
+zig build test-zig0 2>&1 | head -20
+```
 
-Search `stage0/astgen_test.zig` for lines matching:
+If tests **FAIL**: dispatch a worker (Step 4 below) with context
+describing the failure — no test was "enabled", just paste the first
+~20 lines of output and tell the worker existing tests are failing.
+After the worker returns, follow Steps 5–7 as normal. Re-run Phase 0
+until existing tests pass before proceeding to the main loop.
+
+If tests **PASS**: proceed to the main loop.
+
+## Main Loop
+
+Repeat until no `SkipZigTest` lines AND no commented corpus entries
+remain in `astgen_test.zig`.
+
+### Step 1: Find the next disabled test
+
+Search `stage0/astgen_test.zig` in priority order:
+
+**Priority A — SkipZigTest lines:**
+Search for lines matching:
 ```
 if (true) return error.SkipZigTest
 ```
-Pick the first one. If none found, all corpus tests pass — stop.
+Pick the first one. Note the test name (the `test "..."` header above
+the skip line) and the line number.
 
-Note the test name (the `test "..."` header above the skip line) and
-the line number.
+**Priority B — Commented corpus entries:**
+If no SkipZigTest lines exist, search for lines matching `//.{ "` inside
+the `corpus_files` tuple (between `const corpus_files = .{` and `};`).
+Pick the first one. Note the file name and line number.
 
-### Step 2: Comment it out
+If neither is found, all tests are enabled — go to the final check.
 
-Comment out the `if (true) return error.SkipZigTest;` line to enable
-the test.
+### Step 2: Enable the test
+
+**For SkipZigTest:** Comment out the `if (true) return error.SkipZigTest;`
+line to enable the test.
+
+**For commented corpus entry:** Uncomment the line (remove the leading
+`//`).
 
 ### Step 3: Quick smoke test
 
@@ -46,7 +75,9 @@ without bloating your context. The worker will run the full test itself.
 
 1. Read the file `.claude/skills/port-astgen/worker-prompt.md`.
 2. Replace the placeholder `{{TEST_CONTEXT}}` with the actual context:
-   - Test name and line number from Step 1
+   - What was enabled: test name + line number (SkipZigTest) or
+     corpus file name + line number (corpus entry)
+   - Whether this is a SkipZigTest or a corpus entry
    - The first ~10 lines of test output from Step 3
 3. Launch via the Task tool:
    ```
@@ -60,7 +91,9 @@ The worker returns a structured result. Extract:
 - `STATUS`: one of `pass`, `progress`, or `no-progress`
 - `COMMIT_MSG`: a descriptive commit message
 
-### Step 6: Verify build
+### Step 6: Handle by status
+
+**If STATUS is `pass` or `progress`:**
 
 Launch a sub-agent to run:
 
@@ -72,10 +105,10 @@ This must exit 0 with no unexpected output. The agent must investigate:
 1. Any valgrind errors.
 2. Any debug output (should comment out printf statements).
 3. Any formatting or staticcheck issues.
-3. Any failing tests -- should not happen as agent verifies before returning,
-   but if it does, the sub-agent should fix them.
+4. Any failing tests — should not happen as the worker verifies before
+   returning, but if it does, the sub-agent should fix them.
 
-### Step 7: Commit
+Then commit:
 
 ```sh
 git add stage0/astgen.c stage0/astgen_test.zig
@@ -84,13 +117,33 @@ git commit -m "<COMMIT_MSG from worker>
 Co-Authored-By: <whatever model is running this>"
 ```
 
-### Step 8: Repeat
+**If STATUS is `no-progress`:**
 
-Go back to Step 1. **Never stop early** — continue until all `SkipZigTest`
-lines are gone, all tests are un-commented and all tests pass.
+Do NOT commit. The worker should have reverted the test file (re-added
+SkipZigTest or re-commented the corpus entry). Verify with:
 
-If you decide that "it's done", do a final sanity check:
+```sh
+git diff stage0/astgen_test.zig
+```
+
+If there are leftover changes (the entry is still enabled), re-comment
+the corpus entry or re-add the SkipZigTest yourself. Then:
+
+```sh
+git checkout -- stage0/astgen.c stage0/astgen_test.zig
+```
+
+Log that this test was skipped due to no progress and continue.
+
+### Step 7: Repeat
+
+Go back to Step 1. **Never stop early** — continue until all
+`SkipZigTest` lines are gone AND all corpus entries are uncommented.
+
+## Final Check
+
+When no disabled tests remain, run:
 
     zig build all-zig0 -Dvalgrind
 
-If that fails, go back to 1.
+If that fails, go back to Phase 0 (treat it as a leftover).

stage0/.claude/skills/port-astgen/worker-prompt.md

@@ -4,8 +4,10 @@ You are a worker agent porting `AstGen.zig` to `astgen.c`. This is a
 **mechanical translation** — no creativity, no invention. When the C
 code differs from Zig, copy the Zig structure into C.
 
-The orchestrator has already enabled a corpus test for you. Your job:
-diagnose the failure, port the fix, clean up, and return a result.
+The orchestrator has enabled a test for you (either by uncommenting a
+corpus entry in `corpus_files` or by commenting out a `SkipZigTest`
+line). Your job: diagnose any failure, port the fix, clean up, and
+return a result.
 
 ## Context from orchestrator
 
@@ -67,8 +69,9 @@ Apply the minimal mechanical change to `astgen.c` to match the upstream. Run
 - `string_bytes_len` diff decreased
 - First tag mismatch position moved later
 
-You should mark progress marker (whatever it is from the above) *in/near the
-comment of the skipped test*.
+You should mark progress marker (whatever it is from the above) *in/near
+the disabled test entry* (as a TODO comment on the SkipZigTest line or
+above the commented corpus entry).
 
 Once there is *any* progress, you MUST clean up and commit per sections below.
 Do not try to fix everything at once -- clean up & commit early & often.
@@ -77,8 +80,11 @@ Do not try to fix everything at once -- clean up & commit early & often.
 
 1. Remove ALL `fprintf`/`printf` debug statements from `astgen.c`.
 2. Remove `#include <stdio.h>` if it was added for debugging.
-3. If the test still fails: re-add the `if (true) return error.SkipZigTest;`
-   line with a TODO comment describing the remaining diff.
+3. If the test still fails:
+   - **For a SkipZigTest test:** re-add the `if (true) return error.SkipZigTest;`
+     line with a TODO comment describing the remaining diff.
+   - **For a corpus entry:** re-comment the line in `corpus_files` (add `//`
+     prefix back) and add a TODO comment above it describing the remaining diff.
 4. Test if other compilers or valgrind did not regress, fix if it did:
 
     zig build fmt-zig0 && zig build all-zig0 -Dvalgrind |& grep -v Warning
@@ -92,9 +98,12 @@ STATUS: pass | progress | no-progress
 COMMIT_MSG: <one-line descriptive message about what was ported/fixed>
 ```
 
-- `pass` — the enabled test now passes (SkipZigTest was NOT re-added)
-- `progress` — partial progress was made (SkipZigTest was re-added with TODO)
-- `no-progress` — no measurable improvement (SkipZigTest was re-added)
+- `pass` — the enabled test now passes (SkipZigTest was NOT re-added /
+  corpus entry remains uncommented)
+- `progress` — partial progress was made (SkipZigTest was re-added with
+  TODO / corpus entry was re-commented with TODO above it)
+- `no-progress` — no measurable improvement (SkipZigTest was re-added /
+  corpus entry was re-commented)
 
 ## Rules