knowledge-save

A command for saving one reusable engineering insight in OpenArche, a local store for project knowledge. It records decisions, patterns, solutions, or non-obvious problems in a structured form.

In plain words
What is it for?
Use it to save durable technical decisions, repeatable solutions, engineering patterns, and important gotchas for later retrieval.
Why use it?
It prevents useful lessons from being lost after a task and keeps one-off notes out of the long-term knowledge store.

Command

Install

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.

agentmods
npx agentmods add commands/done-0/openarche/knowledge-save
Clone the repo
git clone --depth 1 https://github.com/Done-0/openarche
Per session 10 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 367 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5 $0.00010 $0.00367
Opus 5 $0.00005 $0.00183
Sonnet 5 $0.00002 $0.00073
Haiku 4.5 $0.00001 $0.00037

Measured 2d ago against content hash 529a4d9d8d2c, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

knowledge-save 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 2d 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.

commands/knowledge-save.md · 54 lines

What it actually says

Use this command to save one explicit piece of reusable engineering knowledge into the local OpenArche store. For repository-specific work, prefer the repository-local store at .openarche/knowledge/. Use the global store only when the user is saving cross-project knowledge on purpose.

What to save:

  • durable decisions
  • reusable patterns
  • non-obvious gotchas
  • high-signal fixes

Do not save:

  • one-off chatter
  • unresolved ideas
  • project-specific notes with no reuse value
  • obvious facts that do not improve future execution quality

When writing a knowledge item, require these fields:

  • title
  • type: solution, decision, pattern, or gotcha
  • structure: atomic, linear, tree, or graph
  • trigger_context
  • tags
  • body

When saving:

  1. Find the correct OpenArche data directory.
  2. Read and validate the current config.
  3. Load the current index.json.
  4. Build the embedding from the same recall text the product uses: title + " " + trigger_context.
  5. Create a new knowledge id unless the user is explicitly updating an existing item.
  6. Write the markdown file under <store>/knowledge/<id>.md.
  7. Write the matching index entry.

If the user is updating an existing knowledge item:

  • keep the existing id stable
  • keep the file name and index id aligned
  • do not silently create a duplicate entry

When reporting back:

  • say whether a new item was created or an existing item was updated
  • show the id
  • summarize the saved title, type, and trigger context
Changes

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.

  1. 2d ago First seen · 54 lines · 10 tokens per session scan A 529a4d9d8d2c

Subscribe to this mod's changes

knowledge-save is a command published in the GitHub repository Done-0/openarche (12 stars, last pushed 4mo ago), licensed MIT. It adds 10 tokens to every session and 367 once invoked, about $0.0001 per session on Opus 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.