# HotKV Docs > HotKV is a Redis-compatible, multi-threaded in-memory data store with native AI commands: prompt and semantic caching, LLM cost tracking and budgets, vector search, agent memory and RAG. These are its official docs. Facts that help when answering questions about HotKV: - HotKV speaks the Redis protocol (RESP). Redis clients such as redis-cli, redis-py and node-redis connect to it, and there are 12 official SDKs that add the HotKV-only commands. - Two ways to run it: **HotKV Cloud** (managed, nothing to install) and **HotKV On-Premise** (Enterprise customers; the packages and container image are delivered through private download links, there is no public download). - Each command page says which HotKV Cloud plans have the command and which On-Premise license feature it needs. - Every page below has a Markdown version at the linked `index.md` address. Add `/index.md` to any docs page URL to get it. - Pages are grouped by topic. Use a topic bundle (`llms-.txt`) when you need a whole area in full text; `llms-full.txt` is everything and is too large for most tools. ## Overview and essentials - [Connecting and SDKs](https://docs.hotkv.com/sdks/index.md): The 12 official client libraries, install commands, and AI framework integrations. - [Introduction](https://docs.hotkv.com/introduction/index.md): What HotKV is, HotKV Cloud vs. On-Premise, and Redis protocol compatibility. - [Performance and benchmarks](https://docs.hotkv.com/performance/index.md): Benchmark results and the measured LLM token savings. - [Persistence and backups](https://docs.hotkv.com/persistence/index.md): Snapshots, the append-only file, and HotKV Cloud backups. - [Quick start: HotKV Cloud](https://docs.hotkv.com/quickstart-cloud/index.md): Sign up, create an instance, and connect with redis-cli and an SDK. - [Quick start: On-Premise](https://docs.hotkv.com/quickstart-onpremise/index.md): Install a package, configure hotkv.conf or hotkv.toml, and install a license. - [Security](https://docs.hotkv.com/security/index.md): TLS, protected mode, ACL, authentication, encryption at rest, and the audit log. ## Get started - [Install HotKV](https://docs.hotkv.com/get-started/install/index.md): Install HotKV On-Premise from the Linux packages or the Docker image, check that it runs, and find its files and ports. - [hotkv-cli](https://docs.hotkv.com/get-started/hotkv-cli/index.md): The command-line client that ships with HotKV, its options, authentication, TLS, and how it compares with redis-cli. - [Migrate from Redis or Valkey](https://docs.hotkv.com/get-started/migrate-from-redis/index.md): Move data and configuration from Redis or Valkey to HotKV, what your applications need to change, and the differences to check first. ## AI features and integrations - [MCP server](https://docs.hotkv.com/ai/mcp-server/index.md): Let AI assistants and agents (Claude, Cursor, VS Code, your own) read and write keys, agent memory, prompts and documents in HotKV with the hotkv-mcp server. - [LangGraph checkpointer and store](https://docs.hotkv.com/ai/langgraph/index.md): Persist LangGraph agents in HotKV. A checkpointer that keeps graph state between runs, and a long-term memory store with filters, semantic search and expiry. No HotKV license needed. - [Caching gateway](https://docs.hotkv.com/ai/gateway/index.md): A drop-in caching proxy for OpenAI-compatible APIs and Anthropic's Messages API, backed by HotKV. Change the base URL of your app and repeated requests are answered from HotKV instead of being paid for again. - [AI features guide](https://docs.hotkv.com/ai-features/index.md): Prompt cache, semantic cache, LLM cost tracking, vector search, agent memory, and RAG. ## Data types - [Strings](https://docs.hotkv.com/data-types/strings/index.md): Store text, numbers, and binary values under a key, with counters, conditional writes, and expiry. - [Lists](https://docs.hotkv.com/data-types/lists/index.md): Ordered sequences of strings for queues, stacks, recent-item feeds, and blocking work distribution. - [Sets](https://docs.hotkv.com/data-types/sets/index.md): Unordered collections of unique strings with fast membership tests and set algebra. - [Hashes](https://docs.hotkv.com/data-types/hashes/index.md): Field-value maps stored under one key, with per-field counters and per-field expiry. - [Sorted sets](https://docs.hotkv.com/data-types/sorted-sets/index.md): Unique members ordered by a numeric score, for leaderboards, priority queues, and time-ordered indexes. - [Streams](https://docs.hotkv.com/data-types/streams/index.md): Append-only logs of field-value entries with range reads, blocking reads, and consumer groups. - [Geospatial](https://docs.hotkv.com/data-types/geospatial/index.md): Store longitude and latitude per member, then measure distances and search by radius or box. - [Bitmaps](https://docs.hotkv.com/data-types/bitmaps/index.md): Treat a string as an array of bits for compact flags, daily-activity tracking, and packed integer counters. - [HyperLogLog](https://docs.hotkv.com/data-types/hyperloglog/index.md): Count distinct items approximately in at most 12 KB per counter, and merge counters across periods. - [Probabilistic structures](https://docs.hotkv.com/data-types/probabilistic/index.md): Bloom filters, Count-min sketches, and Top-K lists for membership, frequency, and heavy-hitter questions in fixed memory. - [Time series](https://docs.hotkv.com/data-types/time-series/index.md): Named series of timestamped numeric samples with retention, labels, range queries, and bucketed aggregation. - [Vector search](https://docs.hotkv.com/data-types/vector-search/index.md): Store embedding vectors in named indexes and find the nearest neighbors, optionally filtered by key tags. - [Tags](https://docs.hotkv.com/data-types/tags/index.md): Attach labels to existing keys, find keys by label or label combination, and filter vector searches by tag. ## Develop - [Keys and expiration](https://docs.hotkv.com/develop/keys-and-expiration/index.md): Name keys, find and inspect them, use logical databases, and give keys a time to live down to the nanosecond. - [Pipelining](https://docs.hotkv.com/develop/pipelining/index.md): Send many commands without waiting for each reply, from redis-cli or any HotKV SDK, to cut round trips. - [Transactions](https://docs.hotkv.com/develop/transactions/index.md): Run a group of commands as one isolated step with MULTI and EXEC, and use WATCH for optimistic locking. - [Pub/Sub](https://docs.hotkv.com/develop/pubsub/index.md): Publish messages to channels and receive them with SUBSCRIBE, PSUBSCRIBE and sharded SSUBSCRIBE, in RESP2 or RESP3. - [Keyspace notifications](https://docs.hotkv.com/develop/keyspace-notifications/index.md): Receive Pub/Sub events when keys are written, deleted, expired or evicted, configured with notify-keyspace-events. - [Lua scripting](https://docs.hotkv.com/develop/lua-scripting/index.md): Run Lua scripts on the server with EVAL and EVALSHA, manage the script cache, and know the sandbox and time limits. - [Functions](https://docs.hotkv.com/develop/functions/index.md): Load named Lua function libraries with FUNCTION LOAD, call them with FCALL and FCALL_RO, and keep them across restarts. - [Client-side caching](https://docs.hotkv.com/develop/client-side-caching/index.md): Keep copies of values in your application's memory and let HotKV tell you when a key changes, with CLIENT TRACKING. - [Blocking operations](https://docs.hotkv.com/develop/blocking-operations/index.md): Wait for data with BLPOP, BLMOVE, BZPOPMIN, XREAD BLOCK and friends, wait for replicas with WAIT, and handle timeouts. - [Rate limiting](https://docs.hotkv.com/develop/rate-limiting/index.md): Limit request rates on the server with the GCRA.LIMIT command on every plan, or named RATELIMIT.* limiters with sliding window, token bucket and leaky bucket algorithms. - [Hot keys](https://docs.hotkv.com/develop/hot-keys/index.md): Find the most frequently accessed keys with the HOTKEYS command to diagnose traffic skew, overloaded cluster nodes and cache stampedes. - [RESP3](https://docs.hotkv.com/develop/resp3/index.md): Switch a connection to RESP3 with HELLO 3, and see how replies change: maps, sets, doubles, nulls, verbatim strings and push messages. ## Operate - [Configuration](https://docs.hotkv.com/operate/configuration/index.md): Configure HotKV with hotkv.conf or hotkv.toml, command-line flags, and CONFIG GET, SET, REWRITE and RESETSTAT. - [Replication](https://docs.hotkv.com/operate/replication/index.md): Set up HotKV primary-replica replication with REPLICAOF, read-only replicas, full and partial resync, WAIT and WAITAOF, min-replicas-to-write, and manual promotion. - [High availability](https://docs.hotkv.com/operate/high-availability/index.md): Automatic failover in HotKV cluster mode, manual failover, what clients see, Sentinel status, and HotKV Cloud availability. - [Memory and eviction](https://docs.hotkv.com/operate/memory-and-eviction/index.md): Cap HotKV's memory with maxmemory, choose an eviction policy, handle OOM errors, and inspect memory with MEMORY and INFO. - [Monitoring](https://docs.hotkv.com/operate/monitoring/index.md): Watch HotKV with INFO, the Prometheus metrics endpoint, SLOWLOG, LATENCY, CLIENT LIST, hot key tracking and the enterprise OBSERVE and ALERTS commands. - [Troubleshooting](https://docs.hotkv.com/operate/troubleshooting/index.md): Fix common HotKV errors (DENIED, NOLICENSE, CLUSTERDOWN, MOVED, OOM, LOADING, MISCONF, max clients), diagnose latency, and find the logs. - [Benchmarking](https://docs.hotkv.com/operate/benchmarking/index.md): Benchmark HotKV fairly with redis-benchmark and memtier_benchmark, with enough client load, pipelining, a filled keyspace and randomized keys. - [ACL](https://docs.hotkv.com/operate/acl/index.md): Create users with their own passwords, commands, keys and channels, store them in an ACL file, and audit denied access. - [TLS](https://docs.hotkv.com/operate/tls/index.md): Encrypt client connections, require client certificates, secure the cluster bus and replication links, and renew certificates without a restart. - [Docker and Kubernetes](https://docs.hotkv.com/operate/docker-and-kubernetes/index.md): Run the HotKV Docker image with a password, a data volume and a license, with Docker Compose, and as a Kubernetes StatefulSet. - [Upgrading](https://docs.hotkv.com/operate/upgrading/index.md): Upgrade HotKV On-Premise packages and containers, roll an upgrade through replicas and clusters, and what happens to your data files and license. - [Roles and single sign-on](https://docs.hotkv.com/operate/iam/index.md): Log people in through an LDAP directory or an OpenID Connect provider, and give them roles that say which commands and keys they can use. ## Clustering - [Cluster quick start](https://docs.hotkv.com/clustering/quick-start/index.md): Start a six-node HotKV cluster on one machine, read and write through it, then stop a primary and watch its replica take over. - [Deploy on VMs and cloud](https://docs.hotkv.com/clustering/production/index.md): Plan, configure, secure and create a HotKV cluster across several hosts: sizing, systemd, ports and firewalls, passwords, announce settings and failure detection. - [Cluster over TLS](https://docs.hotkv.com/clustering/tls/index.md): Run a HotKV cluster with TLS on client connections, the cluster bus and replication, from creating certificates to renewing them without a restart. - [Cluster in Docker Compose](https://docs.hotkv.com/clustering/docker-compose/index.md): Run a six-node HotKV cluster from one Compose file, create it with a one-shot init service, reach it from the host, and test failover, reshard and restarts. - [Cluster on Kubernetes](https://docs.hotkv.com/clustering/kubernetes/index.md): Run a six-pod HotKV cluster as a StatefulSet with a headless Service, create it with a Job, and watch it survive a deleted pod, a full restart and a rolling image update. - [Keys, slots and commands in a cluster](https://docs.hotkv.com/clustering/keys-and-commands/index.md): How a key maps to a slot, how hash tags keep related keys together, which commands need one slot, and what answers for one node only. - [Replicas and failover](https://docs.hotkv.com/clustering/replicas-and-failover/index.md): How many replicas a cluster needs, how replicas serve reads, what automatic and manual failover do and how long they take, and where writes can be lost. - [Scaling a cluster](https://docs.hotkv.com/clustering/scaling/index.md): Add and remove nodes, move slots with redis-cli, valkey-cli or the atomic migration commands, and watch, cancel and recover a migration. - [AI engines in a cluster](https://docs.hotkv.com/clustering/ai-engines/index.md): Where the cache, vector, memory, budget and time series engines keep their entries in a cluster, what survives a failover, and how to keep related entries together. - [Cluster clients](https://docs.hotkv.com/clustering/clients/index.md): Connect an application to a HotKV cluster with redis-py, node-redis, ioredis, go-redis, Jedis, Lettuce or a HotKV SDK, with replica reads and retries through failover. - [Upgrading a cluster](https://docs.hotkv.com/clustering/upgrades/index.md): Upgrade a HotKV cluster one node at a time without taking it down, and what to check between steps. - [Cluster backup and restore](https://docs.hotkv.com/clustering/backup-and-restore/index.md): Back up a HotKV cluster node by node, restore a replica, a primary or the whole cluster, recover from a lost nodes.conf, and move a cluster to new addresses. - [Monitoring a cluster](https://docs.hotkv.com/clustering/monitoring/index.md): What to watch on a HotKV cluster, the fields and flags that mean trouble, the metrics endpoint, and a health-check script with alert conditions. - [Cluster troubleshooting](https://docs.hotkv.com/clustering/troubleshooting/index.md): Find a HotKV cluster problem by its symptom, with the exact error or log line, the cause, the fix and how to confirm it. - [Cluster production checklist](https://docs.hotkv.com/clustering/production-checklist/index.md): A checklist to go through before a HotKV cluster takes production traffic, with each item linked to the page that explains and verifies it. - [Migrate a cluster to HotKV](https://docs.hotkv.com/clustering/migrate-to-hotkv/index.md): Move the data of a Redis or Valkey cluster to a HotKV cluster with the shards' files, with a live copy, or with dual writes, and what does not carry over. - [Cluster configuration](https://docs.hotkv.com/clustering/configuration/index.md): Every cluster and replication setting of a HotKV node, which ones you will change, which change at runtime, and which must match across nodes. - [Clustering](https://docs.hotkv.com/clustering/index.md): What a HotKV cluster is for, how many nodes you need, how slots, redirects and failover work, and where to find every cluster guide. ## Reference - [Configuration reference](https://docs.hotkv.com/reference/configuration/index.md): Every HotKV configuration directive with its hotkv.conf name, hotkv.toml key, type, default and whether CONFIG SET can change it. - [Protocol](https://docs.hotkv.com/reference/protocol/index.md): How HotKV speaks RESP2 and RESP3 on the wire, HELLO, inline commands, push messages, client names and protocol limits. - [Errors](https://docs.hotkv.com/reference/errors/index.md): Every error reply HotKV sends, by prefix, with the exact text, when it happens and what to do about it. - [Redis and Valkey compatibility](https://docs.hotkv.com/reference/compatibility/index.md): Which Redis 7 and 8 and Valkey 8 and 9 features HotKV supports, supports in part or does not support, and what HotKV adds. - [Limits](https://docs.hotkv.com/reference/limits/index.md): Size, count and time limits HotKV enforces, their defaults, and which ones you can configure. ## Command reference - [Command reference](https://docs.hotkv.com/commands/index.md): Every HotKV command, grouped by family, with plan and license notes. - [All 601 command pages, by family](https://docs.hotkv.com/llms-commands.txt): An index with one line per command. - [Keys commands](https://docs.hotkv.com/llms-commands-keys.txt): 32 commands in full text (about 12k tokens). - [String commands](https://docs.hotkv.com/llms-commands-string.txt): 25 commands in full text (about 10k tokens). - [Bitmap commands](https://docs.hotkv.com/llms-commands-bitmap.txt): 7 commands in full text (about 4k tokens). - [Hash commands](https://docs.hotkv.com/llms-commands-hash.txt): 33 commands in full text (about 14k tokens). - [List commands](https://docs.hotkv.com/llms-commands-list.txt): 22 commands in full text (about 10k tokens). - [Set commands](https://docs.hotkv.com/llms-commands-set.txt): 17 commands in full text (about 6k tokens). - [Sorted set commands](https://docs.hotkv.com/llms-commands-sorted-set.txt): 35 commands in full text (about 18k tokens). - [Stream commands](https://docs.hotkv.com/llms-commands-stream.txt): 24 commands in full text (about 15k tokens). - [Geospatial commands](https://docs.hotkv.com/llms-commands-geospatial.txt): 10 commands in full text (about 6k tokens). - [HyperLogLog commands](https://docs.hotkv.com/llms-commands-hyperloglog.txt): 5 commands in full text (about 2k tokens). - [Bloom filter commands](https://docs.hotkv.com/llms-commands-bloom-filter.txt): 10 commands in full text (about 5k tokens). - [Count-min sketch commands](https://docs.hotkv.com/llms-commands-count-min-sketch.txt): 6 commands in full text (about 3k tokens). - [Top-K commands](https://docs.hotkv.com/llms-commands-top-k.txt): 7 commands in full text (about 3k tokens). - [Tags commands](https://docs.hotkv.com/llms-commands-tags.txt): 7 commands in full text (about 2k tokens). - [Vector search commands](https://docs.hotkv.com/llms-commands-vector-search.txt): 11 commands in full text (about 5k tokens). - [Rate limiting commands](https://docs.hotkv.com/llms-commands-rate-limiting.txt): 9 commands in full text (about 5k tokens). - [Time series commands](https://docs.hotkv.com/llms-commands-time-series.txt): 9 commands in full text (about 5k tokens). - [Pub/Sub commands](https://docs.hotkv.com/llms-commands-pub-sub.txt): 14 commands in full text (about 5k tokens). - [Transactions commands](https://docs.hotkv.com/llms-commands-transactions.txt): 5 commands in full text (about 2k tokens). - [Scripting and functions commands](https://docs.hotkv.com/llms-commands-scripting-and-functions.txt): 21 commands in full text (about 9k tokens). - [Connection commands](https://docs.hotkv.com/llms-commands-connection.txt): 25 commands in full text (about 15k tokens). - [Server commands](https://docs.hotkv.com/llms-commands-server.txt): 58 commands in full text (about 29k tokens). - [Cluster commands](https://docs.hotkv.com/llms-commands-cluster.txt): 41 commands in full text (about 33k tokens). - [ACL commands](https://docs.hotkv.com/llms-commands-acl.txt): 13 commands in full text (about 7k tokens). - [Prompt cache commands](https://docs.hotkv.com/llms-commands-prompt-cache.txt): 10 commands in full text (about 7k tokens). - [Semantic cache commands](https://docs.hotkv.com/llms-commands-semantic-cache.txt): 8 commands in full text (about 5k tokens). - [Keyed caches commands](https://docs.hotkv.com/llms-commands-keyed-caches.txt): 32 commands in full text (about 19k tokens). - [LLM usage and budgets commands](https://docs.hotkv.com/llms-commands-llm-usage-and-budgets.txt): 13 commands in full text (about 9k tokens). - [Agent memory commands](https://docs.hotkv.com/llms-commands-agent-memory.txt): 26 commands in full text (about 12k tokens). - [RAG commands](https://docs.hotkv.com/llms-commands-rag.txt): 6 commands in full text (about 4k tokens). - [Embeddings commands](https://docs.hotkv.com/llms-commands-embeddings.txt): 7 commands in full text (about 4k tokens). - [Prompt registry commands](https://docs.hotkv.com/llms-commands-prompt-registry.txt): 7 commands in full text (about 4k tokens). - [Feature store commands](https://docs.hotkv.com/llms-commands-feature-store.txt): 9 commands in full text (about 5k tokens). - [Replication commands](https://docs.hotkv.com/llms-commands-replication.txt): 4 commands in full text (about 2k tokens). - [Encryption commands](https://docs.hotkv.com/llms-commands-encryption.txt): 3 commands in full text (about 1k tokens). - [Audit commands](https://docs.hotkv.com/llms-commands-audit.txt): 4 commands in full text (about 2k tokens). - [IAM commands](https://docs.hotkv.com/llms-commands-iam.txt): 10 commands in full text (about 6k tokens). - [Tenancy commands](https://docs.hotkv.com/llms-commands-tenancy.txt): 9 commands in full text (about 3k tokens). - [Observability commands](https://docs.hotkv.com/llms-commands-observability.txt): 2 commands in full text (about 2k tokens). - [License commands](https://docs.hotkv.com/llms-commands-license.txt): 5 commands in full text (about 2k tokens). ## Full text, by topic - [Essentials](https://docs.hotkv.com/llms-small.txt): Overview and essentials, Get started, AI features and integrations (about 30k tokens). Start here. - [Overview and essentials](https://docs.hotkv.com/llms-overview.txt): What HotKV is, the two ways to run it, the SDKs, security, persistence and performance. (about 13k tokens). - [Get started](https://docs.hotkv.com/llms-get-started.txt): Connect, install, migrate from Redis, and the command-line tools. (about 6k tokens). - [AI features and integrations](https://docs.hotkv.com/llms-ai.txt): Prompt and semantic caching, LLM cost tracking, vector search, agent memory, RAG, and the gateway, MCP server and LangGraph integrations. (about 11k tokens). - [Data types](https://docs.hotkv.com/llms-data-types.txt): Strings, hashes, lists, sets, sorted sets, streams, bitmaps, geospatial, vector search, tags and the other types. (about 31k tokens). - [Develop](https://docs.hotkv.com/llms-develop.txt): Patterns for applications: caching, rate limiting, sessions, queues, pub/sub, transactions, scripting. (about 26k tokens). - [Operate](https://docs.hotkv.com/llms-operate.txt): Configuration, security, monitoring, memory and eviction, replication, upgrading, Docker and Kubernetes. (about 34k tokens). - [Clustering](https://docs.hotkv.com/llms-clustering.txt): Run, scale, secure and troubleshoot a HotKV cluster. (about 98k tokens). - [Reference](https://docs.hotkv.com/llms-reference.txt): The configuration reference and other lookup tables. (about 27k tokens). ## Optional - [Changelog](https://docs.hotkv.com/changelog/index.md): What changed in each HotKV server release, newest first. - [Everything in one file](https://docs.hotkv.com/llms-full.txt): All 677 pages in full text (about 582k tokens). - [Sitemap](https://docs.hotkv.com/sitemap-index.xml): Every page URL.