Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add alivirgo/Major-AI-Skills --skill binary-file-suppressiongit clone --depth 1 https://github.com/alivirgo/Major-AI-SkillsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/alivirgo/major-ai-skills/binary-file-suppression)<a href="https://agentmods.dev/skills/alivirgo/major-ai-skills/binary-file-suppression"><img src="https://agentmods.dev/badge/skills/alivirgo/major-ai-skills/binary-file-suppression/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/alivirgo/major-ai-skills/binary-file-suppression"><img src="https://agentmods.dev/badge/skills/alivirgo/major-ai-skills/binary-file-suppression.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00026 | $0.01414 |
| Opus 5.5 | $0.00010 | $0.00566 |
| Sonnet 5.5 | $0.00005 | $0.00283 |
| Haiku 4.5 | $0.00003 | $0.00141 |
Grade A, and why
binary-file-suppression scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 1mo ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 122 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Binary File Ingestion Suppression (Hex Buffer Guard)
Overview
When an autonomous agent mistakenly attempts to read a compiled binary (.exe, .wasm, .pyc), SQLite database (.sqlite), media asset (.png, .mp4), or compressed archive (.tar.gz, .zip) into text context, standard tokenizers attempt to decode raw byte streams into UTF-8 characters.
This causes immediate Context Poisoning: thousands of unrenderable replacement tokens (\ufffd, \x00, \x0f) flood the context window, blowing past token limits, degrading model attention weights, and causing model hallucination loops.
The Binary Suppression Protocol enforces pre-flight binary detection via magic bytes and null-byte heuristics, replacing raw file contents with clean structural metadata.
Raw Binary Ingestion vs. Metadata Guard
┌─────────────────────────────────────────────────────────────┐
│ Binary Ingestion Comparison │
│ │
│ Unprotected Binary Read (`cat app.sqlite`): │
│ SQLite format 3\x00\x10\x00\x01\x01\x00@ \x00\x00\x00... │
│ ↳ 45,000 Garbage Tokens Ingested into Context │
│ ↳ Context Poisoned, Attention Destroyed, $1.50 Wasted │
│ │
│ Binary Guard Interception: │
│ [BINARY ARTIFACT SUPPRESSED] │
│ • Path: `data/app.sqlite` │
│ • Format: SQLite 3 Database (Magic: `SQLite format 3`) │
│ • Size: 4.2 MB (4,404,019 bytes) │
│ ↳ 25 Clean Metadata Tokens Ingested (99.9% Protection) │
└─────────────────────────────────────────────────────────────┘
The 3-Tier Binary Detection Ladder
┌───────────────────────────────────────────────────────────────────────────┐
│ 1. EXTENSION BLACKLIST: `.wasm`, `.pyc`, `.dylib`, `.so`, `.png`, `.mp3` │
│ 2. MAGIC BYTE SIGNATURES: Check first 16 bytes for ELF, SQLite, ZIP, PNG │
│ 3. NULL-BYTE HEURISTIC: If $>0$ null bytes (`\x00`) in first 8KB $\rightarrow$ Binary│
└───────────────────────────────────────────────────────────────────────────┘
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 1mo ago Changed · -8 tokens per session 16d485c73f94
- 1mo ago First seen · 122 lines · 34 tokens per session scan A 45d5b3180967
binary-file-suppression is a skill published in the GitHub repository alivirgo/Major-AI-Skills (2 stars, last pushed today), licensed MIT. It adds 26 tokens to every session and 1,414 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-05.
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