redact-secret · Report

Personal API key (phx_)

phx_ + 42–49 of [0-9A-Za-z] (base57 since 2026-03-30, base62 before); the phc_ project token is public and never claimed.

PostHog
Detectors: posthog-token
Run 2026-10-07
Mode published · redact-secret 0.1.0-beta.14

All providers

Dossier verdictReady
Dossier evidence levelT1 · Provider-documented
Dossier researched2026-09-28

Registry detector posthog-token since redact-secret#906 (registry pinned at 1127bf9); graduated from a Beta.11 arrival family (#434 slice d, #860 Tier A handoff), contract in benchmarks/lib/beta8/434d.ts. T1. Peers lag: trufflehog 3.97.4 reads phx_ + 43–48 over [a-zA-Z0-9_], missing 42- and 49-byte keys.

New pipelineAuthority

Built from the new pipeline

The new pipeline is the authority for credential qualification. These numbers are read from the qualification view derived from the official credential-eval run of the public-evidence-snapshot population. The regression and policy populations keep their own counts on the qualification pages and are not added in here.

Authority: new
Population: public-evidence-snapshot
Engine: credential-eval 0.1.0-alpha.16
Evidence: snapshot-2026.10.06.4
Run: sha256:4bec6e539482…
Recorded: 2026-10-07
Authorised for: @redact-secret/core@0.1.0-beta.14

Maintainer-reviewed (independent review pending)

598 fixtures of the 7,041 in evidence release snapshot-2026.10.06.4 carry this label. They are counted in the numbers on this page.

Passed the project’s own verification (source evidence, automated checks, recorded counter-arguments); not yet independently reviewed.

OpenRedaction default (all patterns): not measured in this run (optional)

The default (all-pattern) profile is slow and noisy for credential evaluation: personal data and resource identifiers dominate its findings, and its last official measurement took 7 minutes of scanner time on a population the credential profile scans in seconds (its methods run takes 40+ minutes), so it is a manual measurement and never blocks other scanners or core verification (#763). Its earlier results stay as history with their run identity; the credential profile is a separate scanner, never spliced with it.

Last measurement: policy-corpus@linux-x64 (configuration sha256:2451ce7bf380), public-evidence-snapshot+methods@linux-x64 (configuration sha256:d47d081ce5fb), public-evidence-snapshot@linux-x64 (configuration sha256:2451ce7bf380), regression-corpus@linux-x64 (configuration sha256:2451ce7bf380) · engine 0.1.0-alpha.5 · recorded 2026-10-05 · retained record, no longer listed by the run registry. It stays labelled with that run identity and is never combined with another profile or another run.

Open the qualification page for this pointer

OpenRedaction credential profile (33 types): not measured in an official run (local exploratory diagnostics only: see ADR)

The credential profile is the comparison profile chosen in docs/decisions/2026-10-06-choose-the-openredaction-credential-bearing-profile-as-the-comparison-scanner.md. It is optional in the official run class because no pinned engine configuration measures it yet: making it required would refuse every official view until the owner approves the one profile-only run. Its own history starts with that run; nothing of the default's is reused for it.

No earlier measurement of it is recorded. Nothing is shown in its place.

Official measurement: pending: requires owner approval (one profile-only run; see the decision).

Open the qualification page for this pointer

Every population and its qualification

Research record

From credential-evidence snapshot-2026.10.06.4 · records at 77ce761 · schema 1.8.0. It describes the research on the format, not what any scanner or the product does, and not a support status.

Review stateDraft, not reviewed
Format revision1 · current
ResearchResearched
Researched2026-09-28

3 events in the review history: 2 observed, 1 reviewed. Latest: observed on 2026-09-28 by automation, project maintainer. Project-maintained review is not independent validation. The family record at this release.

Format

Provider format research from credential-evidence snapshot-2026.10.06.4 · records at 77ce761 · schema 1.8.0.

What it looks like

Descriptive pattern: ^phx_[0-9A-Za-z]{42,49}$

Parts are shown as recorded. Evidence classes belong to the facts below; no class is assigned to a part.

Format facts

Provider documented · provider-source · current · observed 2026-09-28
PERSONAL_API_KEY_PREFIX = "phx_" and generate_random_token_personal() at 658715d (re-checked 2026-09-28); docs name phx_: the docs document the phx_ personal API key; provider code and unit tests (ruling R1) fix the base57/base62 alphabet and the algorithm from which the 42–49 band is derived
- PostHog/posthog @ 658715dd3b434e0a5ada471981d4053b70e72034: posthog/models/utils.pyprovider-documentation · last read 2026-09-28 · latest outcome read · supports the docs document the phx_ personal API key; provider code and unit tests (ruling R1) fix the base57/base62 alphabet and the algorithm from which the 42–49 band is derived
Unresolved · tool-corroboration · current · observed 2026-09-28
Pinned scanner rules are consistent with the contract grammar (1 artifact: trufflehog 3.97.4).
- trufflesecurity/trufflehog @ v3.97.4: pkg/detectors/posthog/posthog.goscanner-rule-source · last read 2026-09-28 · latest outcome read · supports trufflehog 3.97.4: PostHog: \b(phx_[a-zA-Z0-9_]{43,48})\b (no phs_; misses 42- and 49-byte bodies; admits _)
Provider documented · field-prefix · current · observed 2026-09-28
prefix: phx_
- PostHog/posthog @ 658715dd3b434e0a5ada471981d4053b70e72034: posthog/models/utils.pyprovider-documentation · last read 2026-09-28 · latest outcome read · supports prefix: phx_
- posthog.com/docs/api/personal-api-keysprovider-documentation · last read 2026-09-28 · latest outcome read · supports personal API key
Provider documented · field-alphabet · current · observed 2026-09-28
alphabet: base57 [2-9A-HJ-NP-Za-km-z] since 2026-03-30; base62 [0-9A-Za-z] in the earlier prefixed eras; the contract is the union [0-9A-Za-z]
- PostHog/posthog @ d610b45e4c72: posthog/models/utils.pyprovider-sdk-source · last read 2026-09-28 · latest outcome read · supports base62
- PostHog/posthog @ 658715dd3b434e0a5ada471981d4053b70e72034: posthog/models/utils.pyprovider-documentation · last read 2026-09-28 · latest outcome read · supports BASE57 = base62 minus 0 1 O I l; test_uses_base57_alphabet
- github.com/redact-secret/redact-secret/issues/860issue-or-discussion · last read 2026-09-29 · latest outcome read · supports R1 · #issuecomment-5852413851
Provider documented · field-body · current · observed 2026-09-28
body: 42–49 bytes: base57 era 48 or 49; 35-byte base62 era at most 48 (47 ≈ 88.6%); 32-byte base62 era at most 43 (42 ≈ 1.6%) (Per-length shares derived from the T1 algorithm. Shorter bodies (below 0.03% of any era) are an accepted false negative and are asserted by no fixture; 41 and 50 back length twins.)
- PostHog/posthog @ 1.43.0: posthog/models/utils.pyprovider-sdk-source · last read 2026-09-28 · latest outcome read · supports body: 42–49 bytes: base57 era 48 or 49; 35-byte base62 era at most 48 (47 ≈ 88.6%); 32-byte base62 era at most 43 (42 ≈ 1.6%)
- PostHog/posthog @ d610b45e4c72: posthog/models/utils.pyprovider-sdk-source · last read 2026-09-28 · latest outcome read · supports body: 42–49 bytes: base57 era 48 or 49; 35-byte base62 era at most 48 (47 ≈ 88.6%); 32-byte base62 era at most 43 (42 ≈ 1.6%)
- PostHog/posthog @ 658715dd3b434e0a5ada471981d4053b70e72034: posthog/models/utils.pyprovider-documentation · last read 2026-09-28 · latest outcome read · supports generate_random_token(35), forced top bit; test_exact_length
- github.com/PostHog/posthog/pull/52495provider-sdk-source · last read 2026-09-28 · latest outcome read · supports base57 since 2026-03-30
Provider documented · field-separators · current · observed 2026-09-28
separators: none inside the body; no checksum
- PostHog/posthog @ 658715dd3b434e0a5ada471981d4053b70e72034: posthog/models/utils.pyprovider-documentation · last read 2026-09-28 · latest outcome read · supports separators: none inside the body; no checksum
Unresolved · field-boundary · current · observed 2026-09-28
boundary: a key glued to an identifier on either side ([A-Za-z0-9_-]) is not claimed; a 50+ run is rejected, never truncated
- redact-secret/redact-secret @ 270faf84dc12f6a4a4cf61fe3ffab7aadc4f7262: docs/audits/evidence/860/posthog.mdprovider-documentation · last read 2026-09-28 · latest outcome read · supports implementation notes
Provider documented · field-project-token · current · observed 2026-09-28
project-token: phc_ is the project token, public by design ("ok to be public"); never claimed (Benign controls outside credential-named assignments only: under a credential-named key generic detection redacts it today, which is generic-token's verdict, not this family's.)
- redact-secret/redact-secret @ 270faf84dc12f6a4a4cf61fe3ffab7aadc4f7262: docs/audits/evidence/860/posthog.mdprovider-documentation · last read 2026-09-28 · latest outcome read · supports decision: phc_ stays benign
- posthog.com/docs/apiprovider-documentation · last read 2026-09-28 · latest outcome read · supports project-token: phc_ is the project token, public by design ("ok to be public"); never claimed
Unresolved · field-deferred-prefixes · current · observed 2026-09-28
deferred-prefixes: pha_/phr_ OAuth tokens and phh_ are outside this handoff (No fixture asserts either reading.)
- redact-secret/redact-secret @ 270faf84dc12f6a4a4cf61fe3ffab7aadc4f7262: docs/audits/evidence/860/posthog.mdprovider-documentation · last read 2026-09-28 · latest outcome read · supports deferred-prefixes: pha_/phr_ OAuth tokens and phh_ are outside this handoff
Tool corroborated · field-peer-lag · current · observed 2026-09-28
peer-lag: trufflehog 3.97.4 reads phx_ + [a-zA-Z0-9_]{43,48}: it misses 49-byte base57 keys and 42-byte base62 keys and admits _; it has no phs_ alternative. gitleaks 8.30.1 has no PostHog rule (Corroboration only; never used to narrow or widen the contract.)
- gitleaks/gitleaks @ v8.30.1: config/gitleaks.tomlscanner-rule-source · last read 2026-10-04 · latest outcome read · supports no posthog rule
- trufflesecurity/trufflehog @ v3.97.4: pkg/detectors/posthog/posthog.goscanner-rule-source · last read 2026-09-28 · latest outcome read · supports peer-lag: trufflehog 3.97.4 reads phx_ + [a-zA-Z0-9_]{43,48}: it misses 49-byte base57 keys and 42-byte base62 keys and admits _; it has no phs_ alternative. gitleaks 8.30.1 has no PostHog rule
Unresolved · listed-references · current · observed 2026-09-28
The legacy contract lists 12 references without stating which property each supports.
- PostHog/posthog @ 1.43.0: posthog/models/utils.pyprovider-sdk-source · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
- PostHog/posthog @ d610b45e4c72: posthog/models/utils.pyprovider-sdk-source · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
- PostHog/posthog @ 658715dd3b434e0a5ada471981d4053b70e72034: posthog/models/utils.pyprovider-documentation · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
- github.com/PostHog/posthog/pull/52495provider-sdk-source · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
- redact-secret/redact-secret @ 270faf84dc12f6a4a4cf61fe3ffab7aadc4f7262: docs/audits/evidence/860/README.mdproject-research-note · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
- github.com/redact-secret/redact-secret/issues/906issue-or-discussion · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
- github.com/redact-secret/redact-secret/issues/860issue-or-discussion · last read 2026-09-29 · latest outcome read · supports Listed as a reference by the legacy contract · #issuecomment-5852413851
- github.com/redact-secret/redact-secret/issues/860issue-or-discussion · last read 2026-09-29 · latest outcome read · supports Listed as a reference by the legacy contract
- github.com/redact-secret/redact-secret-benchmarks/issues/434issue-or-discussion · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
- redact-secret/redact-secret @ 270faf84dc12f6a4a4cf61fe3ffab7aadc4f7262: docs/audits/evidence/860/posthog.mdprovider-documentation · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
- posthog.com/docs/apiprovider-documentation · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
- posthog.com/docs/api/personal-api-keysprovider-documentation · last read 2026-09-28 · latest outcome read · supports Listed as a reference by the legacy contract
Provider documented · dossier-research · current · observed 2026-09-28
Legacy dossier research (verdict ready, tier T1) cited 3 sources; the dossier does not attribute sources to individual properties.
- PostHog/posthog @ 658715dd3b434e0a5ada471981d4053b70e72034: posthog/models/utils.pyprovider-documentation · last read 2026-09-28 · latest outcome read · supports Cited by the legacy dossier research for this family
- github.com/PostHog/posthog/pull/52495provider-sdk-source · last read 2026-09-28 · latest outcome read · supports Cited by the legacy dossier research for this family
- redact-secret/redact-secret @ 8b6a5fde52ecb4dfce13f09c7a947062d21483c7: docs/audits/evidence/860/posthog.mdproject-research-note · last read 2026-09-28 · latest outcome read · supports Final research evidence recorded by the legacy dossier
Provider documented · taxonomy-sources · current · observed 2026-09-28
The legacy taxonomy lists 2 sources for this family. The taxonomy records no date; the dossier researchedAt is used as the observed-at date.
- redact-secret/redact-secret @ 270faf84dc12f6a4a4cf61fe3ffab7aadc4f7262: docs/audits/evidence/860/posthog.mdprovider-documentation · last read 2026-09-28 · latest outcome read · supports Listed as a source for this family in the legacy taxonomy
- posthog.com/docs/api/personal-api-keysprovider-documentation · last read 2026-09-28 · latest outcome read · supports Listed as a source for this family in the legacy taxonomy

Open questions

No open question is recorded for this revision.

Benchmark dossier notes

From the provider dossier, as written. The evidence level above says how well the format is backed; a fact the dossier does not record is not shown.

Shape: phx_ + 42 to 49 alphanumerics, no separator or checksum.
Basis: prefix T1 from docs and code (an SDK error string also states "prefixed with phx_"); alphabet and algorithm T1 from code and unit tests.
Issuance: not attempted; optional check of one key issued today (expect 48 or 49, none of 0 1 O I l).
Contract in core: detector-families.md.

In this benchmark

Fixture rows on the current run. Counts are for redact-secret in published · redact-secret 0.1.0-beta.14 mode.

Fixtures: 44
Left readable: 0
Redacted too much: 0
False alarms: 0

44 fixtures: 17 expect a redaction, 27 must stay quiet. See every row

redact-secret fixture counts by evidence level
Evidence level	Fixtures	Left readable	Too much	False alarms
T1Provider-documented	17	0	0	0
T2Tool-corroborated	19	0	0	0
T3Project policy	8	0	0	0

Every scanner on the same fixtures

In run order. Counts are what each scanner recorded on this family's fixtures, whichever rules it has; a scanner with no rule for the family has nothing to report on it.

Counts per scanner on this family's fixtures
Scanner	Fixtures	Left readable	Too much	False alarms
flare-redactRuntime library · 1.6.1 · Published npm package · secrets-only (pii, generic_assignment disabled) · JavaScript engineNo rule maps to it	44	14	3	0
gitleaksRepository scanner · 8.30.1 · Directory scan · default rulesNo rule maps to it	44	7	0	1
redact-secretProduct measured here · 0.1.0-beta.14 · Published npm package · default detectors1 detector mapped	44	0	0	0
trufflehogRepository scanner · 3.97.4 · Filesystem scan · verification disabled1 rule targets it	44	4	0	1

Looks like it, but isn't

Values the dossier records as resembling this credential without being one.

Collisions: the era-1 unprefixed personal key (43 characters of urlsafe Base64) has no anchor. phc_ must stay unclaimed.

Scanner rules for this family

Mapped by hand (reviewed 2026-09-30) from each scanner's pinned rule file, never from what a scanner found on the fixtures.

Peer scanner rules that target this family
Scanner	Rule	What the rule matches
trufflehog · rules 3.97.4	`posthog`	phx_ + 43-48 characters

No rule maps to this family in flare-redact, gitleaks, openredaction.

Find

Evidence level

Scanners

44 of 44 rows

Fixtures in this family

44 rows, redact-secret's outcome on each. Rows that need a look come first (0), then the rest in corpus order. Choose "Every scanner" to see each scanner's outcome for the same rows.

Fixtures in Personal API key (phx_)
Fixture	Kind and evidence	redact-secret
`posthog-token-actions-env`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-bare-prose`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-bearer-header`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-chat-paste`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-compose-env`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-curl-projects`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-dotenv`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-export`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-json-api-key`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-json-token`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-key-shape-bare`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-key-shape-quoted`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-key-shape-unicode-crlf`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-mcp-config`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-project-token-prefix-twin`posthog · prefix-near-miss	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-sdk-kwarg`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-underscore-in-body-twin`posthog · wrong-alphabet	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-x-api-key-header`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-yaml-config`posthog · documented-format-literal	Must redactT1 · Provider-documented	Redacted
`posthog-token-actions-secret-reference`posthog · templated-reference	Must not flagT3 · Project policy	Quiet
`posthog-token-body-41-twin`posthog · wrong-length	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-body-50-twin`posthog · wrong-length	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-ellipsis-placeholder`posthog · documentation-placeholder	Must not flagT3 · Project policy	Quiet
`posthog-token-env-reference-reference`posthog · templated-reference	Must not flagT3 · Project policy	Quiet
`posthog-token-event-uuid-encoded-value`posthog · benign-encoded-value	Must not flagT2 · Tool-corroborated	Quiet
`posthog-token-host-urls-public-id`posthog · public-identifier	Must not flagT2 · Tool-corroborated	Quiet
`posthog-token-hyphen-in-body-twin`posthog · wrong-alphabet	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-hyphen-prefix-twin`posthog · prefix-near-miss	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-key-guidance-prose`posthog · prose-mention	Must not flagT3 · Project policy	Quiet
`posthog-token-label-prose`posthog · benign-lookalike	Must not flagT3 · Project policy	Quiet
`posthog-token-leading-glue-twin`posthog · boundary-violation	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-mask`posthog · benign-lookalike	Must not flagT3 · Project policy	Quiet
`posthog-token-masked-placeholder`posthog · documentation-placeholder	Must not flagT3 · Project policy	Quiet
`posthog-token-prefix-only`posthog · benign-lookalike	Must not flagT2 · Tool-corroborated	Quiet
`posthog-token-project-token-bare-public-id`posthog · public-identifier	Must not flagT2 · Tool-corroborated	Quiet
`posthog-token-project-token-html-public-id`posthog · public-identifier	Must not flagT2 · Tool-corroborated	Quiet
`posthog-token-project-token-init-public-id`posthog · public-identifier	Must not flagT2 · Tool-corroborated	Quiet
`posthog-token-reference`posthog · benign-lookalike	Must not flagT3 · Project policy	Quiet
`posthog-token-short-body`posthog · benign-lookalike	Must not flagT2 · Tool-corroborated	Quiet
`posthog-token-short-prefix-twin`posthog · prefix-near-miss	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-trailing-glue-twin`posthog · boundary-violation	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-truncated-near-miss`posthog · format-near-miss	Must not flagT2 · Tool-corroborated	Quiet
`posthog-token-unknown-role-prefix-twin`posthog · prefix-near-miss	Must not flagT2 · Tool-corroborated · twin	Quiet
`posthog-token-uppercase-prefix-twin`posthog · prefix-near-miss	Must not flagT2 · Tool-corroborated · twin	Quiet

Sources

Researched 2026-09-28.

Documentation and code

posthog.com/docs/api/personal-api-keys
github.com/redact-secret/redact-secret/blob/270faf84dc12f6a4a4cf61fe3ffab7aadc4f7262/docs/audits/evidence/860/posthog.md
github.com/PostHog/posthog/blob/658715dd3b434e0a5ada471981d4053b70e72034/posthog/models/utils.py
github.com/PostHog/posthog/pull/52495

Research log

redact-secret/redact-secret#860Research issue
redact-secret/redact-secret#906Research issue
redact-secret/redact-secret-benchmarks#434Research issue
Final evidence, pinned to a commit/redact-secret/redact-secret/blob/8b6a5fde52ecb4dfce13f09c7a947062d21483c7/docs/audits/evidence/860/posthog.md