Pi 0.87.0

ChangelogRelease notesSep 21, 2026Pi 0.87.0GitHub releasenpmNew Features

Canonical session context and extension boundaries — Edit model context without rewriting history and add actionable lifecycle hooks. See ContextEditEntry and extension events. Full-transcript context extensions — Use context_with_system for per-request system-message transformations. See context_with_system. Per-model image input limits — Configure cache-safe image resizing per model for attachments, read, and tool-result images. See Image Input Limits.

Breaking Changes

Removed the inherited shouldStopAfterTurn agent option. Use finishTurn and return { action: "end" } instead. finishTurn runs before turn_end but applies the decision afterward, and it also receives error and aborted responses; migrate normal-response predicates by returning undefined for those hard exits. See the @earendil-works/pi-agent-core changelog for a complete before-and-after example. Added ContextEditEntry to the exported SessionEntry union. TypeScript consumers with exhaustive entry switches must handle context_edit; use replacement: null for omission and a content replacement otherwise. Made SessionManager canonical for AgentSession provider context. Assigning session.agent.state.messages no longer replaces future request history; restore with SessionManager.inMemory(cwd, { id }, entries), navigate with session.navigateTree(), or append through session.sessionManager and call session.refreshContext(). Expanded TurnEndEvent with required boundary fields and added AgentBeforeSettleEvent to the exported ExtensionEvent union. Consumers constructing events or exhaustively switching on ExtensionEvent must handle the new shapes. ExtensionRunner.emit() no longer accepts turn_end; host integrations dispatch actionable boundaries with emitBoundary(baseEvent, buildContext). Deferred runs requested from agent_settled handlers until all settled handlers finish. Handlers still observe ctx.isIdle() === true, but no longer see a reentrant agent_start during the same notification dispatch.

Added

Added append-only model-context edits. For example, sessionManager.appendContextEdit(entryId, null) omits one message from future provider context without changing raw history, usage, or UI history. Added actionable turn_end and agent_before_settle extension boundaries. Return { entries: [...event.entries, draft], continue: true } to persist structural entries in order and ensure one next provider request without changing steering or follow-up scheduling. Added retain-none compaction input: sessionManager.appendCompaction(summary, null, tokensBefore) stores the compaction's own ID as its kept boundary. Added the context_with_system extension event, which runs after context handlers on the full transcript including system messages and sends its result verbatim. See context_with_system. Added per-model image resize profiles through inputLimits.images.resize in models.json, applied to file attachments, image reads, and tool-result images (#9631).

Fixed

Fixed string context-edit replacements producing invalid assistant and tool-result message content instead of text blocks. Fixed context-invisible boundary metadata and replacement edits causing newly appended or replaced input to be summarized before its first provider request. Fixed edited-context accounting both discarding valid assistant usage captured after the latest context edit and reusing that usage after a later compaction made it stale. Fixed selected error retries and final length/overflow recovery retaining abandoned model attempts in future provider context; post-run recovery omissions are now persisted without hiding raw transcript history or changing queue scheduling. Fixed context handlers that filter or slice messages dropping the prompt and tool declarations, which after extension-driven compaction left requests without built-in tools or made Codex emit raw tool-call text. Handlers no longer see system messages; Pi restores the prompt and tool state after they run. See context (#9789, #9822). Fixed /bug allowing uploads in offline mode while preserving local zip exports (#9841 by @christianklotz). Fixed idle prompt-cache warming rebuilding expired caches when its timer or an extension decision is delayed. Improved crash diagnostics with hints identifying loaded extensions that appear in the stack trace. Fixed text files beginning with GIF being misclassified as images and omitted from read and CLI @file input (#9755). Fixed malformed prompt template frontmatter being silently ignored instead of reported as a resource warning (#9830 by @christianklotz). Fixed inherited unknown OpenAI-compatible Chat Completions endpoints receiving strict tool schemas unless they explicitly advertise support (#9816).