awesome-openclaw-agents/configs/gpt-5.4

GPT-5.4 Agent Configs

Drop-in OpenClaw configs for OpenAI GPT-5.4 (Codex lineage). If you are migrating from Claude Sonnet 4.6, this is the bundle that needs the most prompt surgery — but once it's dialed in, it's a strong daily driver.

"GPT-5.4 sucks in OpenClaw" — mostly a config problem

If you've been reading r/openclaw this week, you've seen the "GPT-5.4 is unusable" posts. Almost all of them turn out to be config issues, not model issues. Two settings in particular:

thinking=high + fastmode=true is the sweet spot. — @Saboo_Shubham_ on Twitter

That's the combo most of the "actually it's fine now" follow-up posts converge on. This bundle ships those defaults.

Quick Start

1. Make sure you have an OpenAI API key with GPT-5.4 access (it's gated on usage tier as of April 2026).

2. Register the provider:

openclaw provider add gpt \
  --api-key $OPENAI_API_KEY \
  --base-url https://api.openai.com/v1

3. Copy the agent bundle:

cp configs/gpt-5.4/SOUL.md ~/.openclaw/agents/coding-assistant/SOUL.md

4. Run with the recommended flags:

openclaw agent \
  --agent coding-assistant \
  --thinking high \
  --fastmode true \
  --message "Add error handling to this fetch call"

You can also set these permanently in ~/.openclaw/config.yaml:

providers:
  gpt:
    defaults:
      thinking: high
      fastmode: true

Model IDs

Model ID	Notes
gpt-5.4	Default. Use with thinking=high.
gpt-5.4-mini	Cheaper, faster. thinking=medium is usually enough.
gpt-5.4-codex	Codex-tuned variant. Better on raw code, worse on reasoning chains.

Cost Comparison (April 2026)

Model	Input	Output
Claude Sonnet 4.6	$3	$15
GPT-5.4	$2.50	$12
GPT-5.4-mini	$0.50	$2
GPT-5.4-codex	$2	$10

With thinking=high, expect output-token usage to be ~1.5-2x higher than a Sonnet session on the same task (the reasoning tokens are billed). Even so, it tends to come out cheaper than Sonnet overall.

Transition Lessons From Claude Sonnet

This is the section the "Transition from Claude Sonnet to Codex-GPT5.4" Reddit thread actually needed. Concrete changes:

1. Your role prompt is too long. Sonnet loves a rich Identity + Personality section. GPT-5.4 with thinking=high treats a long preamble as constraints to reason about and burns reasoning tokens on it. Cut the SOUL.md preamble in half. The file in this bundle is ~20 lines on purpose.

2. Drop explicit chain-of-thought requests. If your Sonnet prompt says "think step by step" or "explain your reasoning before answering," remove it. GPT-5.4's thinking=high mode already does this internally; asking for it again produces a weird double-think where the visible answer is worse.

3. Tool descriptions need to be tighter. Sonnet infers tool intent from loose descriptions; GPT-5.4 will misuse a tool whose description is vague. Give every tool a one-sentence "use this when X" line.

4. Turn OFF fastmode for hard reasoning tasks. The Twitter sweet-spot quote is for coding. If you are doing architecture design, long analysis, or writing, fastmode=false + thinking=high is better. Coding: fastmode=true.

5. Stop telling it to "be concise." Sonnet takes this as a style hint. GPT-5.4 takes it as a hard limit and will truncate mid-function. Say "return complete code" instead.

Gotchas

• Reasoning tokens are invisible but billed. Your output line count will look small while your bill looks big. That's expected.
• Context poisoning is worse. If GPT-5.4 makes a wrong assumption early in a long session, it will hold onto it harder than Claude does. Start a fresh conversation more often.
• Tool-call streaming is flaky. Some OpenClaw TUI versions render GPT-5.4 tool calls with visible latency spikes. Update to 2026.4.11+.

Related Threads

• r/openclaw "Lessons learned: Transition from Claude Sonnet to Codex-GPT5.4"
• Twitter @Saboo_Shubham_ on the thinking=high + fastmode=true combo

Files in This Bundle

• SOUL.md — lean coding-assistant tuned for GPT-5.4's reasoning budget
• .env.example — OpenAI API key