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 Abilityai/cornelius --skill scope-mountgit clone --depth 1 https://github.com/Abilityai/corneliusWrote 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/abilityai/cornelius/scope-mount)<a href="https://agentmods.dev/skills/abilityai/cornelius/scope-mount"><img src="https://agentmods.dev/badge/skills/abilityai/cornelius/scope-mount/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/abilityai/cornelius/scope-mount"><img src="https://agentmods.dev/badge/skills/abilityai/cornelius/scope-mount.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 | $0.00097 | $0.02846 |
| Opus 5.5 | $0.00039 | $0.01138 |
| Sonnet 5.5 | $0.00019 | $0.00569 |
| Haiku 4.5 | $0.00010 | $0.00285 |
Grade A, and why
scope-mount 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 8d 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 — 129 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Scope Mount
ℹ️ First, set expectations: print one line with this skill's version and its most recent change - the top of
metadata.changelog- e.g.scope-mount v1.0 — recent: initial four-role contract. Then proceed. (Skip the banner when applied silently inside a consuming skill.)
Purpose
The scope primitive (ARCHITECTURE.md → "Scope") was built for hygiene: keep the core fingerprint and q-learning clean of encountered material. Its engine default is fail-closed - unset BRAIN_READ_SCOPE → core. That default is correct for the engine and wrong as a retrieval policy, and until 2026-09-04 it was the retrieval policy for every everyday read: /recall, /advise, /decide and eight other skills carried no mount and so read 1,187 of ~6,800 notes. Everything the user has read (Books, Document Insights) and every reference record was invisible to advice and recall. Nobody chose that.
This file is the policy of record for what a read mounts (ARCHITECTURE.md → "Scope Mount Policy"). The engine keeps failing closed; the mount is declared in the playbook, per read, by role.
Contract rule (the reasoning-checks / SOURCE-AUTHORITY.md pattern): this file is the single source of truth. Consuming skills reference it and put the mount inline on their search commands; they never copy the tables. Change a mount here, not in consumers.
State Dependencies
| Source | Location | Read | Write |
|---|---|---|---|
| Scope registry | resources/local-brain-search/memory_config.py → SCOPE_REGISTRY (tokens: core, books, document-insights, company, canon, thinkers, meta, inbox, output; families accept Books/<slug>, Company/<sub>) |
✓ | |
| Company record titles | Brain/Company/**/*.md |
✓ | |
| Thinker roster | Brain/Thinkers/THINKERS-INDEX.md |
✓ | |
| Book shelf | Brain/Books/<slug>/ |
✓ | |
| Similarity contract | resources/local-brain-search/SIMILARITY-CALIBRATION.md |
✓ |
Never writes. Never changes the engine default.
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 8d ago First seen · 129 lines · 97 tokens per session scan A 499b6bff70cb
scope-mount is a skill published in the GitHub repository Abilityai/cornelius (110 stars, last pushed 8d ago), licensed MIT. It adds 97 tokens to every session and 2,846 once invoked, about $0.0004 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 2026-10-09.
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