StopTimizer

Precise token counting using official tokenizers as source of truth from software kernel.

Purpose

Provides accurate token counts for LLM models (GPT, Claude, Gemini) without approximation. Does not perform validation or judgment—returns raw numbers only (Unix philosophy).

Usage

Count All Models

deno run --allow-net <url>/stoptimizer.ts "hello world"
# Output: 2 2 2 2 2 2 2 (space-separated: gpt-5 gpt-5.2 gpt-5-mini gpt-4o gpt-4 gpt-3.5 claude)

JSON Output

deno run --allow-net <url>/stoptimizer.ts --json "test"
# Output: {"gpt-5":1,"gpt-5.2":1,"gpt-5-mini":1,"gpt-4o":1,"gpt-4":1,"gpt-3.5":1,"claude-3.5-sonnet":1}

Single Model

deno run --allow-net <url>/stoptimizer.ts --model gpt-4o "text"
# Output: 1

stdin Support (Large Files)

For files too large for command-line arguments, use stdin:

# Using dash (Unix tradition)
cat KERNEL.md | deno run --allow-net <url>/stoptimizer.ts -

# Using --stdin flag (modern clarity)
deno run --allow-net <url>/stoptimizer.ts --stdin < large-file.txt

# Combined with other options
cat prompt.txt | deno run --allow-net <url>/stoptimizer.ts - --json
cat README.md | deno run --allow-net <url>/stoptimizer.ts --stdin --model gpt-4o

Supported Models

GPT Models (OpenAI)

• gpt-5 - GPT-5 (o200k_base encoding, 100% precise)
• gpt-5.2 - GPT-5.2 (o200k_base encoding, 100% precise)
• gpt-5-mini - GPT-5 mini (o200k_base encoding, 100% precise)
• gpt-4o - GPT-4o (o200k_base encoding, 100% precise)
• gpt-4 - GPT-4 (cl100k_base encoding, 100% precise)
• gpt-3.5 - GPT-3.5 Turbo (cl100k_base encoding, 100% precise)

Other Models

• claude-3.5-sonnet - Claude 3.5 Sonnet (100% precise via Anthropic tokenizer)
• gemini-2.0-flash - Gemini 2.0 Flash (research in progress, use Vertex AI API)

Encoding Note: GPT-5 family and GPT-4o use o200k_base (2.3 MB vocabulary), while GPT-4 and GPT-3.5 use cl100k_base (1.1 MB vocabulary). Token counts will differ between encodings for the same text.

STOP Protocol Validation

Tool provides counts only. Compose validation logic in shell scripts:

#!/bin/bash
# Example: STOP validation with stdin (for large prompts)

OLD=$(cat prompt-v1.txt | deno run --allow-net <url>/stoptimizer.ts - --model gpt-4o)
NEW=$(cat prompt-v2.txt | deno run --allow-net <url>/stoptimizer.ts - --model gpt-4o)

if [ "$OLD" -eq "$NEW" ]; then
  CHARS_OLD=$(wc -c < prompt-v1.txt)
  CHARS_NEW=$(wc -c < prompt-v2.txt)
  GAIN=$((CHARS_NEW - CHARS_OLD))
  echo "✅ STOP COMPLIANT: Both $OLD tokens, gained $GAIN chars"
  exit 0
else
  echo "❌ STOP VIOLATION: $OLD vs $NEW tokens"
  exit 1
fi

CI/CD Integration

# .github/workflows/stop-validation.yml
name: STOP Protocol Validation
on: [pull_request]

jobs:
  validate:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: denoland/setup-deno@v1
      
      - name: Validate prompt changes
        run: |
          TOOL_URL="https://raw.githubusercontent.com/ShipFail/promptware/main/os/skills/stoptimizer/stoptimizer.ts"
          
          # Check each optimization
          deno run --allow-net $TOOL_URL --model gpt-4o "args" > /tmp/old
          deno run --allow-net $TOOL_URL --model gpt-4o "arguments" > /tmp/new
          [ "$(cat /tmp/old)" -eq "$(cat /tmp/new)" ] || exit 1

Performance

• First run: 2-3 MB download (vocabularies cached in `/.cache/deno/`)
• Subsequent runs: Instant (cached modules)
• Memory: ~10-15 MB runtime
• Speed: ~100-200 tokens/sec per model

Exit Codes

• 0 - Success (token count returned)
• 2 - Error (network failure, invalid model, missing argument)

Limitations

• Requires network access on first run for vocabulary download
• Gemini tokenizer requires additional research (SentencePiece WASM integration)
• Text-only (no multimodal token counting)
• No streaming support (processes entire text at once)

References

• RFC 0022: STOP Protocol
• RFC 0012: Skill Specification
• js-tiktoken
• OpenAI Tokenizer

Examples

Basic Token Counting

$ deno run --allow-net stoptimizer.ts "The quick brown fox"
5 5 5 5

Comparing Abbreviations vs Full Words

$ deno run --allow-net stoptimizer.ts --json "params"
{"gpt-4o":1,"gpt-4":1,"gpt-3.5":1,"claude-3.5-sonnet":1}

$ deno run --allow-net stoptimizer.ts --json "parameters"
{"gpt-4o":1,"gpt-4":1,"gpt-3.5":1,"claude-3.5-sonnet":1}

# Both tokenize to 1 token - STOP compliant!

Programmatic Use

import { Tiktoken, getGPTVocab } from "./deps.ts";

const vocab = getGPTVocab("cl100k_base");
const tokenizer = new Tiktoken(
  vocab.bpe_ranks,
  vocab.special_tokens,
  vocab.pat_str
);

const tokens = tokenizer.encode("hello world");
console.log(`Token count: ${tokens.length}`);
tokenizer.free();