The Codex 5.2 restyle in ad9df3f68 watered down the four deep-work
exhortations from gpt-5.4 (tool_call_philosophy, tool_persistence,
dependency_checks, dig_deeper) into a single bullet, leaving the
'deep worker' identity without behavioral teeth.
Restore them as Codex-style sub-sections under Exploration:
- Tool-call discipline: more calls = more accuracy, retry on partial,
read more files than needed.
- Dig deeper: don't stop at first plausible answer, check second-order
issues, prefer root over symptom (with concrete example).
- Dependency checks: resolve prerequisites before acting.
- Anti-duplication: extracted from inline paragraph to its own block.
LSP clean. 267 -> 315 lines.
Previous prose-dense rewrite went too far in stripping bullet structure.
Codex 5.1/5.2 prompts (the closest reference for an OpenAI deep-worker
prompt) actually use bullets liberally - just well-grouped (4-6 per list)
with prose introductions on each section. Restructure 5.5 to mirror that
style and tone while preserving Hephaestus's identity and all behavioral
rules from the prior round.
Sections lifted directly from Codex 5.1/5.2 organization:
- # How you work / ## Personality at the top for tonal priming
- # AGENTS.md spec as a standalone section with its own bullets
- ## Autonomy and Persistence with prose intro + Three-attempt sub-protocol
- ## Responsiveness with Frequency, Tone, Content, Examples sub-blocks
(examples rewritten to Hephaestus voice: 'Walking the agents/ tree',
'Found the dispatch in createSisyphusAgent', etc.)
- ## Plan tool with 'use a plan when' bullet list
- ## Validating your work with approval-mode granularity
(non-interactive / interactive / test-related)
- ## Presenting your work with categorical Final answer rules
(Section Headers / Bullets / Monospace / File references / Tone /
Verbosity / Don't)
- # Tool Guidelines as separate top-level section
Hephaestus-specific content preserved verbatim:
- Forge god identity, deep-worker / executor framing
- task() restricted to research subagents only
- Three-attempt failure protocol
- End-to-end usage gate (interactive_bash / playwright / curl / driver)
- Anti-duplication rule on parallel exploration
Amp-derived rules kept compact in their own ## Pragmatism and Scope:
- Smallest correct change, duplication > premature abstraction
- Default-no-tests with explicit exceptions
- WIP-not-legacy rule
- Multi-agent dirty worktree safety
Metrics: 110 -> 267 lines (still -14% from original 312), 4 -> 100 bullets
(grouped Codex-style, not scattered), 24 headers. 38/38 verification
checks pass; LSP clean.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Prior 5.5 prompt enumerated rules across 60+ bullets and 312 lines, which
fights GPT-5.5's strength: it follows prose instructions reliably and does
not need rule-by-rule cataloging. Rewrite as flowing paragraphs while
preserving the deep-worker identity and every load-bearing behavior.
Identity preserved:
- Forge god mythology ("Your boulder is code", "forge it until done")
- Direct executor, not orchestrator (research subagents only)
- Senior-colleague tone, end-to-end persistence
Behaviors preserved (compressed to prose):
- Three-attempt failure protocol → 1 paragraph
- Anti-duplication on parallel exploration
- End-to-end usage gate (interactive_bash / playwright / curl / driver)
- Implementation gate: when delegated, execute directly, no draft loop
Net additions distilled from Amp + Codex 5.2 evolution:
- Pragmatism block: smallest correct change, duplication > premature
abstraction, do not over-engineer, do not validate impossible scenarios
- Default-no-tests: add tests only when user asks, fixes a subtle bug,
or protects an important boundary; never to codebases without tests
- WIP-not-legacy: earlier unreleased shapes in the same turn are drafts,
not legacy contracts requiring backward compatibility
- Multi-agent worktree: continue task without reverting unknown changes
- Code-review mode trigger: "review" → findings-first, severity-sorted
- Personality-first opener (Codex 5.2 pattern) for tonal priming
Metrics: 312 → 110 lines (-65%), 60+ bullets → 4 bullets, 21,803 → 15,654
chars (-28%). 26/26 verification checks pass.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Hephaestus is the autonomous deep-worker - everything it receives is a
delegation. Existing 'Manual behavior' bullet vaguely said 'actually run
it' but left the validation surface unspecified, which lets a checked-in
diff plus passing tests masquerade as completion on user-visible work.
Add a dedicated 'End-to-end usage is the gate' subsection in Codex prose
style (no threats/CAPS, contract frames). Surface determines tool:
- TUI / CLI → interactive_bash (tmux), drive it like a real user
- Web / browser / UI → playwright skill, drive a real browser session
- HTTP API / service → curl or integration script against running service
- Library / SDK → minimal driver script
Reinforce in Forbidden stops trailer: when receiving a delegation,
execute directly and validate through the gate; do not loop back with
a draft when the work is yours to do.
Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)
Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>
Ground-up rewrite that follows the same Codex-style section structure
as the new gpt-5-5 sisyphus prompt, tuned for Hephaestus's autonomous
deep-worker role.
Distinctive elements:
- 'Autonomy and Persistence' section with named 'Forbidden stops' list
(replaces gpt-5-4's FORBIDDEN/CORRECT table rhetoric)
- 'Three-attempt failure protocol' codified
- 'Exploration-first approach' with explicit 5-15 minute expectation
- 'Dig deeper' subsection for root-cause bias
- 'Ambition vs precision' distinction for greenfield vs existing
codebase work
getHephaestusPromptSource() now checks gpt-5-5 before gpt-5-4; the
regex-based gpt-5-4 path stays as the catch-all for other native
versions.
YeonGyu-Kim