FT.SPELLCHECK

Performs spelling correction on a query, returning suggestions for misspelled terms

Browse all commands · Upstream source documentation

Reference field	Value
Canonical name	FT.SPELLCHECK
Catalog group	Search commands
Upstream since	1.4.0 — upstream Redis/module version, not an ffkv release
Pinned catalog	Redis 8.10.0

Syntax

FT.SPELLCHECK index query [DISTANCE distance] [TERMS <INCLUDE |
  EXCLUDE> dictionary [terms [terms ...]]] [DIALECT dialect]

ffkv behavior and limits

Search worker configuration controls a real Rayon pool; GC schedules generation-fenced Rust compaction, not a POSIX fork. Search indexes and documents are bounded and RAM-resident; upstream syntax is not a promise of every option combination or Redis module ABI parity.

Source: README.md:375–377, 636–642; src/engine/search/; tests/bdd/features/search.feature.

All requests share the 8 MiB framing/1,024-argument ingress limit; normal RESP replies have 64 MiB wire/logical budgets with bounded nesting/value counts. Management and Lua origins impose smaller budgets. These are not a process RSS cap. Catalog inclusion is not exhaustive option or wire-format parity. See limits and compatibility.

Metadata availability

This command is in the canonical catalog but has no matching entry in the pinned src/command_metadata.json. Argument flags, complexity and key specifications are not invented. Use the syntax, upstream source documentation and actual scenario evidence below.

BDD coverage and source examples

These are source observations, not a test run performed by this documentation build. A tag identifies scenario intent; an extracted vector identifies a command invocation, which may intentionally produce an error. Scenarios may require setup, multiple connections, persistence, cluster nodes or native-module fixtures.

• Dictionaries supplement real document-frequency spelling suggestions — tests/bdd/features/search.feature:321; command tag and invocation observed.

Extracted command vectors

The following JSON arrays are the test harness’s argument vectors, not shell commands. Numeric arguments are converted by the harness; objects of the form {"base64":"…"} represent decoded binary bytes, not a literal JSON command argument. Preserve scenario setup and connection ordering. See the CLI guide for shell quoting and binary stdin. No reply is invented or inferred.

Dictionaries supplement real document-frequency spelling suggestions — tests/bdd/features/search.feature:335 (I execute:)

[
  "FT.SPELLCHECK",
  "idx",
  "helo",
  "TERMS",
  "INCLUDE",
  "words"
]

Next source assertion: the reply contains:

[["TERM","helo",[["1","hello"],["0","help"]]]]