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 modeled-information-format/mnemonic --skill custodiangit clone --depth 1 https://github.com/modeled-information-format/mnemonicWrote 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/modeled-information-format/mnemonic/custodian)<a href="https://agentmods.dev/skills/modeled-information-format/mnemonic/custodian"><img src="https://agentmods.dev/badge/skills/modeled-information-format/mnemonic/custodian/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/modeled-information-format/mnemonic/custodian"><img src="https://agentmods.dev/badge/skills/modeled-information-format/mnemonic/custodian.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 | $0.00058 | $0.01107 |
| Opus 5.5 | $0.00023 | $0.00443 |
| Sonnet 5.5 | $0.00012 | $0.00221 |
| Haiku 4.5 | $0.00006 | $0.00111 |
Grade A, and why
custodian 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 13d 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 — 141 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Memory
Search first: /mnemonic:search {relevant_keywords}
Capture after: /mnemonic:capture {namespace} "{title}"
Run /mnemonic:list --namespaces to see available namespaces from loaded ontologies.
Custodian Skill
Provides custodial services for the mnemonic memory system: auditing, validation, link repair, decay management, relocation, and summarization.
When to Use
- Proactively when session_start reports low health scores or potential duplicates
- On request when user asks about memory health, broken links, or maintenance
- After project renames to relocate memories and update references
- Periodically to keep decay scores current and identify orphaned memories
Architecture
The custodian operates through focused Python modules:
| Module | Responsibility |
|---|---|
memory_file.py |
Parse/validate/update MIF frontmatter |
link_checker.py |
Build UUID/slug index, validate links, find orphans |
decay.py |
Calculate exponential/linear/step decay, update strength |
relocator.py |
Move files + update all cross-references |
validators.py |
MIF schema validation, ontology relationship checks |
report.py |
Structured findings with markdown/JSON output |
custodian.py |
CLI orchestrator dispatching to modules |
Subcommands
audit (default)
Runs all checks in a single pass. This is the recommended entry point.
/mnemonic:custodian audit [--fix] [--dry-run]
Checks performed:
- Frontmatter: Required fields, UUID format, type enum, date format
- Links: Wiki-links resolve to existing memories
- Relationships: Types match MIF built-in or ontology-defined types
- Decay: Recalculates strength values using configured model
- Orphans: Detects memories with no incoming references
relocate
Moves memories when project or org names change:
/mnemonic:custodian relocate <old-path> <new-path> [--dry-run]
What ships with it
8 files 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.
- 13d ago Changed 5f87e8988354
- 14d ago Changed · +3 lines 49e15774dd60
- 1mo ago First seen · 138 lines · 58 tokens per session scan A ba3b643871a3
custodian is a skill published in the GitHub repository modeled-information-format/mnemonic (23 stars, last pushed 9d ago), licensed MIT. It adds 58 tokens to every session and 1,107 once invoked, about $0.0002 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 2026-08-30.
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