**Overall Verdict:** Accept — The submission is complete, internally consistent, reachable on a single Python 3.12 machine, and objectively evaluated through isolated exact-output tests.

**Completeness Check:**
- Instruction: Complete — Defines the six PII categories, exact replacement token, preservation rules, input, and required output filename.
- Inputs: Complete — `chat_log_raw.txt` and `PII_EXHAUSTIVE_LIST.md` are readable ASCII files with matching manifest sizes and clearly defined roles.
- Toolchain: Complete — Python 3.12 standard library and `re` are sufficient; no credentials, network access, or special hardware are required.
- Reference output: Complete — `chat_log_golden.txt` matches the raw transcript’s targeted substitutions, and the grader embeds the expected mutation output.
- Rubric: Complete — The 20/40/40 static, golden-path, and mutation phases provide objective checks with an explicit passing threshold.

**File and Task Reachability:**
Attachments are `reachable`, and the end-to-end task is `reachable`. I inspected `chat_log_raw.txt`, `chat_log_golden.txt`, `PII_EXHAUSTIVE_LIST.md`, `zero_shot_failure_log.txt`, and `pii_grader.py`. All five are regular, readable ASCII files matching their manifest byte counts; none is an archive, encrypted container, or unsupported format, and no content was left unreviewed. The raw and golden files are consistent line-for-line, while the grader’s four injected mutation cases cover the documented SSN, name/DOB, phone, email/URL, card/license, and Bates-number traps. Uploaded code was not executed; Python execution was unavailable in the review environment, so runtime behavior was assessed from the readable grader source. This is a reviewer-tooling limitation, not a contributor-side blocker. The grader’s isolated workflow supplies the solver only the script and raw input, then checks the required output exactly.

License keys, accounts, tokens, and other credentials are not required from the contributor.  
Confidential, proprietary, or internal material may be evaluated as submitted evidence without requiring additional disclosure.

**Special Screening:**
None

**Recommended Changes:**
The rulebook, fixtures, reference output, and evaluator form a coherent deterministic benchmark with appropriate preservation traps. No changes are required.