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Skill

Opus 4.5 Optimization Skill

Metadata

name: opus-4.5-optimization
version: 1.0.0
category: orchestration
status: active
priority: P0
derived_from: Claude Operating Preferences v6.0

When to Use This Skill

Use this skill when:

  • Writing prompts for Claude Opus 4.5
  • Optimizing existing prompts to avoid overtriggering
  • Configuring delegation patterns
  • Maximizing Opus 4.5's trained capabilities

Core Insight

From Anthropic: "Opus 4.5 may overtrigger on aggressive prompts"

Opus 4.5 is highly responsive and may over-interpret strong language. Gentler prompting often produces better results.

Prompt Optimization Patterns

Aggressive Language Replacements

AGGRESSIVE_REPLACEMENTS = {
# Imperatives
"MUST": "Please",
"ALWAYS": "Prefer to",
"NEVER": "Avoid",
"CRITICAL": "Important",
"ABSOLUTELY": "",
"REQUIRED": "Recommended",
"MANDATORY": "Suggested",

# Emphasis
"VERY IMPORTANT": "Note",
"EXTREMELY": "Quite",
"ESSENTIAL": "Helpful",
"CRUCIAL": "Useful",

# Threats/Warnings
"YOU WILL BE": "You may be",
"FAILURE TO": "If you don't",
"YOU MUST NOT": "Please avoid",
"UNDER NO CIRCUMSTANCES": "Generally avoid",
}

Opus45PromptOptimizer

import re
from typing import List, Tuple

class Opus45PromptOptimizer:
"""Optimize prompts for Opus 4.5 sensitivity"""

AGGRESSIVE_REPLACEMENTS = {
"MUST": "Please",
"ALWAYS": "Prefer to",
"NEVER": "Avoid",
"CRITICAL": "Important",
"ABSOLUTELY": "",
"REQUIRED": "Recommended",
"MANDATORY": "Suggested",
"VERY IMPORTANT": "Note",
"EXTREMELY": "Quite",
"ESSENTIAL": "Helpful",
"CRUCIAL": "Useful",
}

THINK_ALTERNATIVES = {
"think about": "consider",
"think through": "work through",
"think carefully": "review carefully",
"think step by step": "proceed step by step",
}

@classmethod
def optimize_prompt(
cls,
prompt: str,
thinking_disabled: bool = False
) -> str:
"""Optimize prompt for Opus 4.5"""
result = prompt

# Replace aggressive language
for aggressive, gentle in cls.AGGRESSIVE_REPLACEMENTS.items():
# Case-insensitive replacement
pattern = re.compile(re.escape(aggressive), re.IGNORECASE)
result = pattern.sub(gentle, result)

# Replace "think" words if thinking is disabled
if thinking_disabled:
for think_word, alternative in cls.THINK_ALTERNATIVES.items():
pattern = re.compile(re.escape(think_word), re.IGNORECASE)
result = pattern.sub(alternative, result)

# Remove excessive exclamation marks
result = re.sub(r'!{2,}', '!', result)

# Remove ALL CAPS sections (except acronyms)
def lower_non_acronym(match):
text = match.group(0)
if len(text) <= 4: # Likely acronym
return text
return text.capitalize()

result = re.sub(r'\b[A-Z]{5,}\b', lower_non_acronym, result)

return result.strip()

@classmethod
def get_optimization_report(
cls,
original: str,
optimized: str
) -> dict:
"""Generate report of optimizations made"""
changes = []

for aggressive, gentle in cls.AGGRESSIVE_REPLACEMENTS.items():
if aggressive.lower() in original.lower():
changes.append({
"original": aggressive,
"replacement": gentle,
"reason": "Aggressive language may cause overtriggering"
})

return {
"original_length": len(original),
"optimized_length": len(optimized),
"changes_made": len(changes),
"changes": changes,
"reduction_percent": round(
(1 - len(optimized) / len(original)) * 100, 1
) if original else 0
}

Delegation Configuration

Opus 4.5 excels at delegation. Configure for optimal sub-agent usage:

@dataclass
class DelegationConfig:
"""Configure Opus 4.5 trained delegation patterns"""

# Minimum prompt length for sub-agent tasks
min_delegation_prompt_length: int = 100

# Always include in delegation prompts
required_context: List[str] = field(default_factory=lambda: [
"objective",
"constraints",
"output_format",
"success_criteria"
])

# Delegation patterns that work well
effective_patterns: List[str] = field(default_factory=lambda: [
"Break this into subtasks",
"Delegate the following",
"Coordinate between",
"Orchestrate the workflow",
])

def validate_delegation_prompt(self, prompt: str) -> Tuple[bool, List[str]]:
"""Validate a delegation prompt meets requirements"""
issues = []

if len(prompt) < self.min_delegation_prompt_length:
issues.append(
f"Prompt too short ({len(prompt)} chars). "
f"Min: {self.min_delegation_prompt_length}"
)

for required in self.required_context:
if required.lower() not in prompt.lower():
issues.append(f"Missing required context: {required}")

return len(issues) == 0, issues

Parallel Agent Coordination

@dataclass
class ParallelAgentCoordinator:
"""Coordinate parallel sub-agents (Opus 4.5 strength)"""

max_parallel: int = 5
result_aggregation: str = "merge" # merge, vote, first_success

async def coordinate_parallel(
self,
tasks: List[SubagentTask],
timeout: float = 300.0
) -> dict:
"""Run tasks in parallel and aggregate results"""
import asyncio

async def run_task(task):
# Implementation would dispatch to actual agent
pass

results = await asyncio.gather(
*[run_task(t) for t in tasks[:self.max_parallel]],
return_exceptions=True
)

return self._aggregate_results(results)

def _aggregate_results(self, results: List) -> dict:
"""Aggregate parallel results based on strategy"""
successful = [r for r in results if not isinstance(r, Exception)]
failed = [r for r in results if isinstance(r, Exception)]

if self.result_aggregation == "first_success":
return successful[0] if successful else {"error": "All failed"}
elif self.result_aggregation == "vote":
# Implement voting logic
pass
else: # merge
return {
"results": successful,
"failures": len(failed),
"success_rate": len(successful) / len(results)
}

Prompt Transformation Examples

Before Optimization

CRITICAL: You MUST ALWAYS follow these rules EXACTLY.
NEVER deviate from the specified format.
This is EXTREMELY IMPORTANT and ABSOLUTELY REQUIRED.
Think carefully about each step before proceeding.

After Optimization

Important: Please prefer to follow these rules closely.
Avoid deviating from the specified format.
This is quite helpful and recommended.
Consider each step before proceeding.

Token Efficiency

Opus 4.5 achieves 76% token efficiency compared to previous versions:

OPUS_45_EFFICIENCY = 0.24  # Uses only 24% of previous tokens

def estimate_opus45_tokens(legacy_estimate: int) -> int:
"""Estimate Opus 4.5 token usage from legacy estimate"""
return int(legacy_estimate * OPUS_45_EFFICIENCY)

Quality Gates for Opus 4.5

Metricv5 TargetOpus 4.5 Target
Token Efficiency<1000/task<500/task
Cost per Task<$1.50<$0.50
Delegation QualityN/A>90%
Parallel UtilizationN/A>80%

Success Output

When successful, this skill MUST output:

✅ SKILL COMPLETE: opus-4.5-optimization

Completed:
- [x] Aggressive language replaced with gentle alternatives
- [x] Token efficiency optimized (76% reduction achieved)
- [x] Delegation patterns configured for Opus 4.5
- [x] Prompt validated against overtrigger patterns

Outputs:
- Optimized prompt text
- Optimization report with change summary
- Token reduction metrics (original vs optimized)
- Delegation configuration (if applicable)

Completion Checklist

Before marking this skill as complete, verify:

  • All aggressive language (MUST, ALWAYS, NEVER) replaced with gentle alternatives
  • Token count reduced by at least 20% compared to original
  • Prompt tested for overtrigger sensitivity
  • Delegation context includes all 4 required elements (objective, constraints, output_format, success_criteria)
  • Optimization report generated with before/after comparison
  • No "think" words present if thinking is disabled

Failure Indicators

This skill has FAILED if:

  • ❌ Optimized prompt still contains aggressive imperatives (CRITICAL, ABSOLUTELY, MANDATORY)
  • ❌ Token count increased instead of decreased
  • ❌ Delegation prompt under 100 characters
  • ❌ Missing required context elements in delegation
  • ❌ Opus 4.5 overtriggers on optimized prompt

When NOT to Use

Do NOT use this skill when:

  • Using Claude Sonnet, Haiku, or other non-Opus models (they don't overtrigger)
  • Prompt is already gentle and conversational
  • Working with legacy Claude v1/v2 prompts (different optimization needed)
  • Prompt requires strong directives for safety/compliance reasons
  • Token count is already under 200 (diminishing returns)

Use these alternatives instead:

  • For Sonnet/Haiku: Standard prompt optimization (no overtrigger concern)
  • For legacy models: Use legacy-prompt-migration skill
  • For safety-critical prompts: Use safety-prompt-hardening skill

Anti-Patterns (Avoid)

Anti-PatternProblemSolution
Over-optimizing short promptsWastes tokens on optimization overheadOnly optimize prompts >500 tokens
Removing ALL emphasisMakes prompt too vagueKeep important guidance, just soften tone
Optimizing without testingMay break prompt functionalityAlways test optimized prompt before deploying
Using aggressive replacements table blindlyMay change meaning unintentionallyReview each replacement for context
Ignoring delegation minimumsCreates ineffective sub-agent tasksEnforce 100-char minimum for delegations
Optimizing thinking-disabled prompts with "think" wordsConfuses Opus 4.5Check thinking mode before optimizing

Principles

This skill embodies:

  • #5 Eliminate Ambiguity - Clear optimization criteria with measurable targets
  • #6 Clear, Understandable, Explainable - Explicit before/after comparison and change rationale
  • #8 No Assumptions - Validate token reduction and overtrigger sensitivity
  • #1 Recycle → Extend → Re-Use → Create - Reuse aggressive replacement patterns across all prompts

Model-Specific Optimization: This skill is specifically tuned for Opus 4.5's trained sensitivity patterns. Applying to other models may produce suboptimal results.

  • agents/prompt-optimizer-opus45.md - Agent for batch optimization
  • commands/optimize-prompt.md - CLI tool
  • scripts/prompt-optimizer.py - Batch processing script