Bryan's ask: use Larry on prod data without PHI ever leaving the client box.
Added:
lib/hl7-sanitize.sh — tokenize PHI fields in HL7 messages
lib/hl7-desanitize.sh — reverse op (local view-time unmask)
Tokenization model:
- Replace PHI fields with [[CATEGORY_NNNN]] tokens (MRN, NAME, DOB,
ADDR, PHONE, ACCT, SSN, PROV, VISIT, etc.)
- Same value → same token across messages (deterministic via local
lookup table; analysis can still correlate patients).
- Lookup table at $LARRY_HOME/sanitize/lookup.tsv mode 0600 — never
leaves the client.
- Default PHI rule set covers PID, PV1, NK1, GT1, IN1, OBR, OBX,
DG1, ORC; --rules-file to extend.
- --strict also tokenizes unknown Z segments wholesale.
Prompt-side preprocessing in larry.sh:
- {{phi:VALUE}} inline marker, auto-category lookup
- {{phi:CATEGORY:VALUE}} explicit category
- Replaced with the token BEFORE the user input enters conversation
history. The original never reaches the API.
- Local feedback "phi> {{phi:...}} → [[TOKEN]]" printed to terminal only.
New REPL slash commands:
/phi <value> tokenize a single value, print the token
/unmask <token> show original (local terminal only, never API)
/tokens show full PHI ↔ token lookup table
New tools in larry.sh schema:
hl7_sanitize agent can sanitize a file before reading PHI
tokenize-value / detokenize-value (subcommands of hl7-sanitize.sh)
Persona update (agents/larry.md):
- Documented PHI mode and rules for proactive sanitize-first behavior
MANUAL.md updated with the full PHI section including limitations.
Brings total native tools to 29.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Bryan Johnson
b9415f3b57