v0.59.0

Pi Subagents 0.59.0 makes scripted workflows easier to run, watch, and recover. You can now add host-owned command steps to workflow scripts, build parallel sequential lanes, and see clearer status for child sessions and worktree handoffs. Long-running delegation should feel less fragile when contexts reload, providers abort, files are missing, or Windows temporarily locks an output file. This release also improves live controls for non-TUI and RPC hosts.

Highlights

• Run host commands from workflow scripts with safer saved output and clearer command results.
• Build sequential parallel workflows with runs.lanes(...), launch preflight labels, and better retained-resume behavior.
• See cleaner async status, child labels, and worktree handoff details without extra setup.
• Recover more reliably from stale contexts, provider aborts, missing outputs, malformed MCP metadata, and Windows file locks.
• Control live workflow children from more places, including non-TUI and RPC hosts.

Full changelog

Highlights

• Run host commands from workflow scripts with safer saved output and clearer command results.
• Build sequential parallel workflows with runs.lanes(...), launch preflight labels, and better retained-resume behavior.
• See cleaner async status, child labels, and worktree handoff details without extra setup.
• Recover more reliably from stale contexts, provider aborts, missing outputs, malformed MCP metadata, and Windows file locks.
• Control live workflow children from more places, including non-TUI and RPC hosts.

Added

• Add runs.host(...) command steps to workflowScript, with required timeouts, saved output, and status and receipt evidence (#1648).
• Add CI and gate monitor rows that record monitor kind, terminal verdict, freshness, and report pointers in workflow status and receipts.
• Persist workflow lane metadata in child status, receipts, and existing worktree handoff manifests, including display-only worktree paths and branches.
• Add runs.lanes(...) for parallel sequential workflow stages with per-lane results and retained-resume support (#1633).
• Add display-only preflight lane metadata for workflowScript launches, with coverage warnings and planned-lane rendering in launch, status, and live-card views.
• Add a plan-only worktree.cleanup management action that records a cleanup plan without removing worktrees or branches.
• Give every subagent child session a human-readable display name, and include it in result, progress, status, workflow, nested, and intercom payloads. Thanks to @yanqianglu for #1615.
• Add /subagents-steer <run-id> [--child <child-id>] <message> so non-TUI sessions and RPC hosts can steer live async runs. Thanks to @yanqianglu for #1608.
• Add explicit allowNestedSubagents agent authorization for nested fanout without replacing inherited tools or extensions. Thanks to @tutu359 for #1587.
• Accept a child id on /subagents-stop <run-id> <child-id> so one child of a multi-child async run can be stopped without stopping the whole run. Thanks to @yanqianglu for #1603.

Changed

• Reduce noisy launch, status, output, settings, and worktree cleanup messages without changing behavior.
• Include a direct resumable child id in missing workflow receipt guidance when retained status proves it is safe.
• Clarify workflowScript contracts for retained resume keys and durable child output paths.
• Record merge or supersession evidence in existing worktree handoff manifests and show cleanup eligibility without removing anything.
• Show optional lane and work-item context in async status rows, including phase, gate, next action, output, run reference, and stale or blocked state.
• Show workflow child labels and phases in async status progress while preserving stable workflow keys.
• Remove assistant turn budgets, including hard termination, wrap-up prompt injection, and launch configuration.
• Split internal launch, status, settlement, evidence, and direct-MCP planning code into smaller modules without changing public behavior.

Fixed

• Match detached workflow completion by exact child identity, keep host gate rows in snapshots, and report missing host verdicts as inconclusive.
• Replace explicit runs.host(...) output files atomically inside their verified directory, and retry transient Windows destination locks.
• Reject malformed MCP direct-tool server and metadata-cache fields when JSON is loaded.
• Preserve live composite child tool-call ids for cursor-native, so Cursor MCP results keep matching pending execs. Thanks to @moofone for #1677 and #1678.
• Ignore stale cached UI contexts during background status refresh and session lifecycle cleanup (#1670).
• Compact workflow preflight status in default TUI and status views while keeping full details available when expanded (#1668).
• Give runs.lanes(...) stage-0 retained-resume validation actionable runs.run(...) guidance instead of a generic error (#1657).
• Remove the remaining lane: prefix from operator-facing async status rows in the TUI (#1658).
• Allow scheduled project roots shared through a registered Git worktree's .pi symlink while rejecting unrelated or unproven Git-layout escapes. Thanks to @sususu98 for #1656.
• Include delegated child usage in subagent tool results and /subagent-cost, including completed async workflow children and parent compaction usage with persisted workflow-receipt recovery when needed (#1662, #1666). Thanks to @Geraldo-Morais for #1662 and @jf88888 for #1666.
• Avoid false preflight mismatch warnings for generated runs.lanes(...) stage keys (#1649).
• Accept long host tool-call ids in workflow child summaries, matching the existing 4,096-byte session id bound. Thanks to @SudoKillMe for #1653.
• Keep an async workflowScript continuation live while an awaited child coordinates with its supervisor, so later sequential steps still run (#1634).
• Stop stale extension and slash-command contexts from escaping during reload or session replacement.
• Include saved workflow child output paths and inline previews in completion notices (#1629).
• Format million-scale context limits as 1M instead of 1000k in live status displays.
• Restore active workflow children under their workflow parent in Fleet Status after reload, while keeping unmatched shell rows visible.
• Prefer loaded workspace context over repeated internal workflow keys in async TUI lane rows (#1619).
• Accept path-like Pi session ids up to 4,096 characters when snapshotting background work. Thanks to @dvishoot for #1616.
• Accept bare leaf model ids reported by provider drivers when verifying provider-qualified launch candidates. Thanks to @lallenlowe for #1609.
• Resume compaction-induced child aborts once when retained state is safe, and report the exact recovery blocker otherwise.
• Report aborted or signalled no-output child runs with their terminal stop, stderr, or process signal before missing-output handoff diagnostics.
• Apply globalConcurrencyLimit to workflowScript children launched through runs.run and runs.all, not only legacy multi-child runners. Thanks to @mateominato for #1600.
• Ignore nested .pi and sync-backups directories during agent discovery so stale backup definitions cannot become executable agents. Thanks to @arlishansenn for #1596.
• Let projects layer agent overrides by the active parent model provider without duplicating agent definitions. Thanks to @arichiardi for #1597.
• Let operators configure the default subagent_wait window and report window expiry as non-error active work while preserving strict headless draining. Thanks to @Shujakuinkuraudo for #1591.
• Degrade run status to the stored fan-out budget snapshot when persisted state is unavailable, instead of failing the entire run list. Thanks to @qsgy-edge for #1595.
• Enforce MCP server includeTools and excludeTools policies for child direct-tool grants, including adapter-compatible glob matching. Thanks to @Shujakuinkuraudo for #1590.
• Prevent Fleet prompt audit rendering from crashing on malformed non-string task payloads. Thanks to @bengidev for #1586.
• Resume a retained child session once after a provider or transport abort follows useful progress, without restarting the task or involving the parent model.
• Retry unused fallback models after a provider reports a plain-text 500 or internal server error. Thanks to @rafafortes for #1642.
• Mark missing required child handoffs with useful mutation evidence as partial needs-attention results.