Operational Insights support: The Couchbase MCP Server now supports self-managed Couchbase Operational Insights deployments. Run it with the new operational-insights subcommand (couchbase-mcp-server operational-insights). The subcommand ships in the same package and Docker image as the operational server, and uses its own CB_OPERATIONAL_INSIGHTS_* connection and credential settings, default HTTP port (8001), and set of operational_insights_-prefixed tools. Capella-hosted Operational Insights is not supported. See Operational Insights Overview.

Multiple MCP servers in one package: The couchbase-mcp-server package now hosts more than one server behind CLI subcommands. The operational subcommand is the default, so existing configurations keep working unchanged. See Architecture.

Audit logging: Record tool calls, authorization denials, and guardrail blocks, with the caller identity the server saw, in a dedicated audit log. Audit logging covers both the operational and Operational Insights servers. It writes to stderr, to a file, or to both, and supports both time-based and size-based rotation. Enable it with CB_MCP_AUDIT_LOG_ENABLED. See Audit Logging.

Vertical scaling with workers: The operational server can now run several worker processes on one machine in Streamable HTTP mode. Set CB_MCP_WORKERS or --workers to the number of workers. Workers run in stateless mode, which CB_MCP_STATELESS_HTTP also controls. The Operational Insights server does not support multiple workers. See Scaling with Workers.

Health endpoint: In Streamable HTTP mode, the server now exposes GET /health for liveness probes. The endpoint reports process liveness only, never contacts the cluster, and needs no authentication. See Health Check.

Cluster health and diagnostics tools: The following tools were added to Cluster Setup & Health.

Query and Index tools: The following tools were added: get_active_queries, delete_active_query, and create_query_index. create_query_index creates regular and vector indexes by running SQL++ rather than using the SDK index manager.

Search Operations tools: The following tools were added: list_search_indexes, get_search_index_definition, run_search, upsert_search_index, and drop_search_index.

Vector search: Configure an embedding model when you start the MCP server, then run vector search on the Index service (GSI) with run_vector_query, or on the Search Service with run_vector_search. The server supports the capella, openai, cohere, voyage, and bedrock embedding providers. See Embedding Providers.

Large result handling for Operational Insights: The query tools return the full result by default. Set CB_MCP_OPERATIONAL_INSIGHTS_QUERY_RESULT_MAX_SIZE to limit the result size, up to 4 MB. When a result exceeds the limit, the response reports truncated: true. The async query tools use a 30 second timeout for each request to the cluster, so operational_insights_get_async_query_results can fetch larger results. Set CB_MCP_OPERATIONAL_INSIGHTS_ASYNC_QUERY_RESULT_TIMEOUT or --operational-insights-async-query-result-timeout to change it, up to 600 seconds. To keep a large result out of the conversation, operational_insights_run_query_sync and operational_insights_run_query_async can export it to object storage with the copy_to_* arguments. See Large Result Handling.

Active cluster health checks: get_cluster_health_and_services now actively pings cluster services and reports reachability, latency, and connection details. You can filter the check to specific services with service_types.

Read-only mode coverage: upsert_search_index and drop_search_index are disabled when CB_MCP_READ_ONLY_MODE=true, in line with the other write-capable tools. delete_active_query and create_query_index follow the same rule.

Index listing: list_indexes now returns both vector and non-vector indexes.

Separate Operational Insights log files: The Operational Insights server writes mcp_server_operational_insights.<level>.log by default, so it does not share files with the Operational server.

Restructured documentation: The documentation now has separate Couchbase Server and Operational Insights sections, with shared Reference and Architecture pages.

DA-2232: get_schema_for_collection now takes a num_sample_values argument. It sets the number of example values that the schema reports for each field. Leave it unset to use the server default, or pass 0 to return the structure without example values.

DA-2302: Fixes elicitation, which was not working for tools that require confirmation.

DA-1866: Fixes the KV write tools swallowing all exceptions and returning only False, so callers can now see the underlying cause of a failure.

DA-2307: Fixes mutate_subdocument passing the unsupported create-parents option to array_insert.

create_index: This tool is deprecated. It remains available with a deprecation warning. Use create_query_index instead.

Python 3.10 support: The server now requires Python 3.11 to 3.14, because Python 3.10 reached end of life.

Tools: The following tools were added: lookup_subdocument, mutate_subdocument, create_scope, delete_scope, create_collection, delete_collection, create_index, build_index, drop_index.

OAuth Authentication: This release introduces scope labels to let operators remap the couchbase-mcp:read/couchbase-mcp:write scope strings to match the naming convention used by their IdP.

Logging: This release introduces enhanced logging capabilities for the Couchbase MCP Server, providing better log retention control, granular size management per log level, and persistent environment logging.

DA-1945: Fixes a SQL++ parser error that incorrectly rejected the WITHIN keyword.

DA-1997: Resolves underlying issues with the Lark parser.

DA-2002: Addresses security vulnerability findings reported for the MCP Server.

Fixed a potential SQL++ identifier injection vulnerability in get_schema_for_collection.

Addressed an issue where disabled_tools fails silently instead of blocking.

Fixed non-portability of the Capella root CA path.

Prevent silent fallback to password authentication when client-certificate configuration is incomplete.

Ensures KV write tools return failure reasons rather than just a boolean.

Correct inconsistent operator matching during EXPLAIN evaluation.

Enable previously inactive Bandit security rules.

CB_MCP_LOG_MAX_BYTES is deprecated. While the functionality continues to be supported, it’s recommended to use CB_MCP_LOG_ROTATION_MAX_SIZE_MB.

None in this release.

OAuth Authentication: Secure the Streamable HTTP endpoint with OAuth 2.1 JWT token verification and scope-based authorization (couchbase-mcp:read / couchbase-mcp:write), with optional Protected Resource Metadata (PRM) for Dynamic Client Registration. See OAuth.

Logging: Configurable structured logging with log levels (CB_MCP_LOG_LEVEL), multiple output sinks (CB_MCP_LOG_SINKS — console, file, or both), and file output (CB_MCP_LOG_FILE). See Logging.

None in this release.

None in this release.

None in this release.

Removed CB_MCP_READ_ONLY_QUERY_MODE: The previously deprecated read-only query mode has been removed. Use CB_MCP_READ_ONLY_MODE instead, which blocks all write operations (KV and SQL++). See Read-Only Mode.

Removed SSE transport: The previously deprecated Server-Sent Events (SSE) transport has been removed. Use the Streamable HTTP transport (CB_MCP_TRANSPORT=http) instead.