fix(bin): forward PI_CODING_AGENT_DIR to Pi crewmates

[pperanich]

Intent

Forward PI_CODING_AGENT_DIR onto pi and pi-signed crewmate launches in bin/fm-spawn.sh, only when it is set, exactly mirroring how PR #1195 forwards CLAUDE_CONFIG_DIR for claude crewmates. Motivation: crewmate panes come from the long-lived tmux/herdr daemon and do not inherit the primary's environment, so a firstmate primary started under an alternate Pi profile (PI_CODING_AGENT_DIR pointing at a profile with different settings, packages, extensions, auth) spawned crewmates on the default ~/.pi/agent profile. Verified by reading fm-spawn.sh and backends/tmux.sh (send-keys into a new window of the firstmate session) and by launching a pi worker in a fresh tmux shell. Deliberate decisions: keep the change minimal (no new profile concept, no pinning, unlike the stale PRs #877/#966); apply to both pi and pi-signed since both share the Pi launch template; place the block directly after the CLAUDE_CONFIG_DIR block with a matching comment; never prefix when the variable is unset so the default single-profile path is byte-identical to before. Tests: in tests/fm-spawn-dispatch-profile.test.sh pin PI_CODING_AGENT_DIR empty in run_spawn (opt-in via FM_TEST_PI_CODING_AGENT_DIR) and in the four ad-hoc spawn invocations that already pin CLAUDE_CONFIG_DIR, so assertions never depend on the developer's shell; add three cases mirroring the claude ones: pi forwards when set, pi omits the prefix when unset, a non-pi harness (claude) ignores it. No docs changed, matching PR #1195's file set. Commit follows Conventional Commits with no AI attribution.

What Changed

• Pin PI_CODING_AGENT_DIR in spawn fixtures and cover forwarding, omission, and non-Pi behavior.
• Forward a set PI_CODING_AGENT_DIR to pi and pi-signed crewmates while leaving other launches unchanged.

Risk Assessment

✅ Low: The change is narrowly scoped, matches the CLAUDE_CONFIG_DIR precedent, safely quotes the value, covers both Pi harnesses, preserves the unset path, and adds behavior-level spawn tests.

Testing

After repository bootstrap, the targeted suite and focused cases passed. The base source failed the new forwarding test as expected, while the end-to-end CLI transcript showed the profile prefix on pi and pi-signed launches and nowhere else. The worktree remained clean.

Evidence: End-to-end Pi spawn transcript

Source: End-to-end Pi spawn transcript

CASE pi with alternate profile
spawned evidence-pi-set-z1 harness=pi kind=ship mode=no-mistakes yolo=off window=firstmate:fm-evidence-pi-set-z1 worktree=/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-pi-set/wt
TMUX_PAYLOAD=PI_CODING_AGENT_DIR='/opt/profiles/alternate-pi' env -u CURSOR_AGENT -u CURSOR_INVOKED_AS FM_PI_HARNESS=pi '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-pi-set/fake/fakebin/pi' --tui-mode regular -e '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-pi-set/home/state/evidence-pi-set-z1.pi-ext.ts' "$('~/.no-mistakes/worktrees/74c906478ac0/01M1G1SDSM8C5Q0TKAE006FE9F/bin/fm-operational-input.sh' encode launch-brief < '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-pi-set/home/data/evidence-pi-set-z1/brief.md')"

CASE pi-signed with alternate profile
spawned evidence-pi-signed-set-z2 harness=pi-signed kind=ship mode=no-mistakes yolo=off window=firstmate:fm-evidence-pi-signed-set-z2 worktree=/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-pi-signed-set/wt
TMUX_PAYLOAD=PI_CODING_AGENT_DIR='/opt/profiles/alternate-pi' env -u CURSOR_AGENT -u CURSOR_INVOKED_AS FM_PI_HARNESS=pi-signed '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-pi-signed-set/fake/fakebin/pi-signed' --tui-mode regular -e '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-pi-signed-set/home/state/evidence-pi-signed-set-z2.pi-ext.ts' "$('~/.no-mistakes/worktrees/74c906478ac0/01M1G1SDSM8C5Q0TKAE006FE9F/bin/fm-operational-input.sh' encode launch-brief < '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-pi-signed-set/home/data/evidence-pi-signed-set-z2/brief.md')"

CASE pi with PI_CODING_AGENT_DIR unset
spawned evidence-pi-unset-z3 harness=pi kind=ship mode=no-mistakes yolo=off window=firstmate:fm-evidence-pi-unset-z3 worktree=/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-pi-unset/wt
PROFILE_PREFIX=absent

CASE claude while PI_CODING_AGENT_DIR is set
spawned evidence-claude-pi-set-z4 harness=claude kind=ship mode=no-mistakes yolo=off window=firstmate:fm-evidence-claude-pi-set-z4 worktree=/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.5kdLNh/evidence-claude-pi-set/wt
PI_PROFILE_PREFIX=absent

Evidence: Baseline regression reproduction

Source: Baseline regression reproduction

Baseline regression check: target behavioral test against base fm-spawn.sh
not ok - pi launch did not forward firstmate's PI_CODING_AGENT_DIR to the crewmate pane (missing: 'PI_CODING_AGENT_DIR='/opt/test/pi-work' env -u CURSOR_AGENT -u CURSOR_INVOKED_AS FM_PI_HARNESS=pi '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.lSoIfP/profile-pi-agentdir/fake/fakebin/pi' --tui-mode regular')
--- output ---
env -u CURSOR_AGENT -u CURSOR_INVOKED_AS FM_PI_HARNESS=pi '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.lSoIfP/profile-pi-agentdir/fake/fakebin/pi' --tui-mode regular -e '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.lSoIfP/profile-pi-agentdir/home/state/profile-pi-agentdir-z20.pi-ext.ts' "$('/private/tmp/fm-pi-agentdir-baseline.XvlGVv/bin/fm-operational-input.sh' encode launch-brief < '/private/var/folders/1c/sz9p1x8j1msd9cmf3f8rfgrw0000gn/T/fm-spawn-dispatch-profile.lSoIfP/profile-pi-agentdir/home/data/profile-pi-agentdir-z20/brief.md')"
baseline_exit=1 (expected nonzero)

Evidence: Dispatch-profile test log

Source: Dispatch-profile test log

ok - no --model/--effort records defaults and types the claude launch instructions
ok - non-cursor launches clear inherited Cursor identity markers
ok - relative home overrides ignore CDPATH and become absolute before spawn launch construction
ok - FM_HOME defaults resolve relative paths and preserve absolute spellings
ok - absolute override spellings are preserved in spawn launch paths
ok - unresolvable relative spawn overrides fail with named diagnostics
ok - active crew-dispatch profile requires an explicit harness for ship spawns
ok - active crew-dispatch profile requires an explicit harness for scout spawns
ok - active crew-dispatch profile allows an explicit resolved harness
ok - active crew-dispatch profile allows the legacy positional harness form
ok - active crew-dispatch profile allows the raw launch-command escape hatch
ok - claude receives --model and --effort profile flags
ok - codex receives --model and model_reasoning_effort profile flags
ok - codex omits unsupported max effort instead of passing a bad config value
ok - grok receives --model and --reasoning-effort profile flags
ok - grok omits unsupported max reasoning effort
ok - grok omits unsupported xhigh reasoning effort
ok - cursor receives its model-qualified reasoning class and exact task workspace
ok - cursor refuses model ids absent from its resolved binary's live catalog
ok - cursor preserves the requested model when its live catalog is unreachable
ok - opencode receives --model and omits the unsupported effort axis
ok - pi receives --model and --thinking max profile flags
ok - Pi launch probing omits --tui-mode on older Pi and preserves it on supporting Pi
ok - pi-signed shares Pi launch semantics while preserving its configured and recorded identity
ok - pi-signed refuses safely and actionably when the selected executable is unavailable
ok - pi-signed is a distinct persistent secondmate runtime with shared Pi supervision semantics
ok - batch dispatch forwards shared --harness, --model, and --effort to every pair
ok - claude forwards firstmate's CLAUDE_CONFIG_DIR so the crewmate uses the same credential store
ok - claude omits the config-dir prefix when firstmate runs with the single-store default
ok - non-claude harnesses do not receive the claude CLAUDE_CONFIG_DIR prefix
ok - pi forwards firstmate's PI_CODING_AGENT_DIR so the crewmate uses the same agent profile
ok - pi omits the profile prefix when firstmate runs with the default agent directory
ok - non-pi harnesses do not receive the PI_CODING_AGENT_DIR prefix
ok - active crew-dispatch profile does not block secondmate launches
# all fm-spawn-dispatch-profile tests passed

Pipeline

Updates from git push no-mistakes

✅ **intent** - passed

✅ No issues found.

✅ **Rebase** - passed

✅ No issues found.

✅ **Review** - passed

✅ No issues found.

✅ **Test** - passed

✅ No issues found.

• Repository bootstrap: bin/fm-session-start.sh
• Automated behavior suite: bash tests/fm-spawn-dispatch-profile.test.sh
• Focused selectors: test_pi_forwards_firstmate_coding_agent_dir_when_set, test_pi_omits_coding_agent_dir_prefix_when_unset, and test_non_pi_harness_ignores_coding_agent_dir
• Focused pi-signed spawn assertion through the shared Pi launch path
• Regression reproduction: target test_pi_forwards_firstmate_coding_agent_dir_when_set executed against 54663948647a41e21b289d9992159b1bdc3bb6ca:bin/fm-spawn.sh
• Evidence-producing executable check through fm-spawn.sh and captured tmux payloads for set Pi, set Pi Signed, unset Pi, and Claude

✅ **Document** - passed

✅ No issues found.

✅ **Lint** - passed

✅ No issues found.

✅ **Push** - passed

✅ No issues found.

[greptile-apps]

Confidence Score: 5/5

The PR appears safe to merge with no actionable correctness, security, or repository-policy issues identified.

The new assignment is safely quoted, reaches both supported Pi harnesses through their shared launch path, remains a direct interactive command, and leaves unset and non-Pi launches unchanged.

_{Reviews (1): Last reviewed commit: "fix(spawn): forward PI_CODING_AGENT_DIR ..." | Re-trigger Greptile}