Fireworks AI API keys

• Provider documentation fw_-prefixed API key · observed 2026-09-24 · the provider documents only the fw_ prefix (examples are truncated); no body length or alphabet is stated
• Reference 1
• Reference 2

Graduated arrival contract (registry detector since redact-secret#730). Lexical separability decided before authoring (#212): the fw_ prefix plus a 22- or 24-character alphanumeric body separates a key from the recorded confusables (fw_version/fw_id/fw_spec identifiers, the console's short display prefix, placeholders), none of which carries a 22+ alphanumeric run after fw_. Frozen fields are the provider-documented fw_ prefix and the provider code's startsWith("fw_") check (fireconnect key-type.mjs); the body widths are the two widths seen in a small aggregate observation of public values (n=9, #227 row 17) and stay provisional, so the pattern admits exactly the observed widths and no twin or control asserts silence on any other width (23 is not a negative boundary) or on any body alphabet. No pinned peer has a Fireworks rule. Not claimed: an unprefixed legacy key (GitGuardian lists its detector as "Not prefixed"; unconfirmed) and the fpk_ Fire Pass key (a real, separately scoped secret with no public grammar), which is never a control.