Meko Select Datapack

meko-select-datapack — Pin a datapack for this project (Claude Code)

Meko MCP write tools (memory_*, conversation_*, artifact_*) accept an optional datapack_id. When omitted, the server resolves a per-account default — fine for users with one datapack, wrong for users juggling several. This skill lets the user list, search, and pin a datapack, and makes the choice stick across the entire project via the Meko SessionStart hook.

How persistence works (Claude Code)

The pin is project-scoped, keyed by agent_id. The skill writes:

~/.claude/meko-capture/pin-<slug(agent_id)>.json
{ "datapack_id": "<uuid>", "datapack_name": "<name>", "selected_at": "<iso8601>" }

agent_id is the value the SessionStart hook injected into your additionalContext at the top of this session — for Claude Code it has the shape claude_code:<repo-basename> (e.g. claude_code:meko-mcp-server). The slug is the same string with any character outside [A-Za-z0-9._-] replaced by _ (so claude_code:meko-mcp-server → claude_code_meko-mcp-server).

The Meko SessionStart hook (capture.js) reads pin-<slug>.json using its own derivation of agent_id and prepends an Active datapack block to every fresh turn's additionalContext. Because the pin is keyed by project, not session, it survives:

• /clear and /compact (same project, fresh session UUID — hook re-fires, reads the same file).
• Closing and reopening Claude Code in the same repo.
• Multiple Claude Code windows on the same repo (intentional — they share the pin).

If the user wants different datapacks for two windows on the same repo, that's not what this skill is for: in that case, the user should pass datapack_id="<other-uuid>" explicitly on the calls that need to override.

You don't remember the pin yourself — the hook re-injects it. But you DO need to:

1. Read the injected ### Active datapack block if it's present.
2. Pass datapack_id="<id>" on every Meko MCP tool call that accepts it (memory_*, knowledgebase_search, conversation_*, artifact_*) unless the user explicitly says "use a different datapack just for this call." This is non-negotiable — passing the param is what makes the pin actually take effect.
3. Never invent a datapack_id if no block was injected — fall back to the server's default by omitting the parameter.

When to invoke this skill

Trigger immediately on any of these signals:

• User says "switch datapack", "change datapack", "use datapack X", "select datapack", "pick a datapack".
• User says "list my datapacks", "what datapacks do I have", "show me my datapacks".
• User says "which datapack am I on", "which datapack is active", "what's pinned".
• User says "clear datapack", "unpin datapack", "stop using ".
• The first Meko MCP write of a session and no ### Active datapack block was injected AND the user has more than one datapack — proactively offer to pin one. (Single-datapack users get auto-selected; see below.)

Do NOT invoke this skill for routine reads on an already-pinned project — the hook already injected the pin, just use it.

The flow

1. List

datapack_list(conversation_id="<your conversation_id>")

The deployed Meko server returns an array of objects. The fields the skill uses:

• datapack_id — the UUID. This is what gets written to the sidecar and passed as datapack_id to Meko tools.
• datapack_name — human-readable name.
• created_at — ISO timestamp.
• grant — role string ("owner", etc.) — the actual authorization field. Display this verbatim in the Role column. Do not invent or normalize it.
• Count fields (memory_count, knowledge_count, learnings_count, collective_memory_count) — the list handler on Meko doesn't compute any of them (they'd need per-datapack queries; only Describe runs those). All four arrive as stale zeros; the MCP client strips them from the list response so callers aren't misled. Use datapack_describe(datapack_id=...) when you need real counts for a specific datapack.

If the response has zero entries, tell the user: "You don't have any datapacks yet. Run datapack_create(name='<name>') to make one, or visit the Meko Cloud console." Stop.

If the response has exactly one entry, auto-select it. Print: "Only one datapack: <name>. Auto-selecting. Run the skill again with clear to unset." Skip the table; jump straight to step 4 (persist) and step 5 (confirm).

2. Render the table

For 2+ datapacks, render a numbered table. Page size 10. Default sort: created_at DESC (newest first). The columns are exactly:

#   Name                                   Role    Created       Active?

Do NOT add columns that aren't in this list. Note that memory_count / knowledge_count are NOT on the list response — call datapack_describe per-datapack if the user asks for real counts.

Determine the pin state first (before printing anything). Read the ### Active datapack block from your additionalContext if present, else cat ~/.claude/meko-capture/pin-<slug(agent_id)>.json (see step 4 for slug computation). Then print one of these two header lines verbatim, exactly as shown — copy them word-for-word, do not paraphrase:

• No pin set → No datapack currently pinned to this project (working directory).
• Pin set → Currently pinned to this project (working directory): <datapack_name> (<datapack_id>).

Then a blank line, then the table:

No datapack currently pinned to this project (working directory).

Your datapacks (showing 1-10 of 14):

#   Name                                   Role    Created       Active?
1   meko-local-setup                       owner   2026-04-30
2   meko_default_datapack                  owner   2026-04-30
3   prod-research                          owner   2026-04-12
…

Reply with: a number (1-10) to pin · a substring to search · `next` / `prev` to page
            · `clear` to unset · `cancel` to leave the current pin alone

When a pin exists, mark its row in the table with ← (pinned) in the Active? column.

For datapacks beyond the first 10, paginate. For substring matches, re-render the filtered subset numbered from 1.

3. Parse the user's reply

• Integer in range → that row is the choice.
• Substring → re-render with the filter applied. If the filter narrows to exactly one row, treat that as the choice (announce it: "One match: <name>. Pinning.").
• next / prev → re-render the next/previous page.
• cancel → leave any existing pin in place; print "Cancelled. Active datapack unchanged." and stop.
• clear / none / unpin → delete the pin file (see step 4); print "Datapack pin cleared. Agent-driven calls can use the server default now; automatic capture will switch on the next new session." and stop.
• Unrecognized → re-prompt with the legend.

4. Persist

Compute the pin file path. The slug is the SessionStart-injected agent_id with any character outside [A-Za-z0-9._-] replaced by _:

# Take agent_id from the SessionStart-injected block (e.g. "claude_code:meko-mcp-server")
AGENT_ID='claude_code:meko-mcp-server'    # ← inject the actual value verbatim
SLUG=$(printf '%s' "$AGENT_ID" | sed -E 's/[^A-Za-z0-9._-]+/_/g; s/^_+|_+$//g')
DIR="$HOME/.claude/meko-capture"
PIN="$DIR/pin-$SLUG.json"
TMP="$PIN.tmp"
mkdir -p "$DIR"

Then write the file atomically (tmp + rename so a crashed write never leaves a half-file the hook can't parse):

cat > "$TMP" <<JSON
{
  "datapack_id": "<datapack_id>",
  "datapack_name": "<datapack_name>",
  "selected_at": "$(date -u +%Y-%m-%dT%H:%M:%SZ)"
}
JSON
mv "$TMP" "$PIN"

For clear, delete the file: rm -f "$PIN".

5. Confirm

Pinned datapack `<name>` (`<uuid>`) for this project (agent_id=<agent_id>).

The Meko SessionStart hook will re-inject this after `/clear`, `/compact`, and
Claude Code restart. Agent-driven Meko calls in this session should pass
`datapack_id="<uuid>"` immediately; automatic capture routing switches on the
next new session because an existing conversation cannot move between datapacks.

The pin is project-scoped (keyed by agent_id), so other Claude Code windows
in this same repo will pick up the same pin on their next hook fire.

To switch: run `meko-select-datapack` again.
To unpin:  run `meko-select-datapack` and reply `clear`.

The active-datapack block won't appear in the current turn's additionalContext (the hook only fires on session-start / pre-compact / session-end), so for the rest of this turn the agent must remember to pass datapack_id itself. Tell the user: "This turn I'll pass datapack_id="<uuid>" manually; automatic capture will use it in the next new session."

Edge cases

• Zero datapacks — print onboarding hint with datapack_create syntax. Stop.
• Network failure on datapack_list — surface the error verbatim ("Couldn't reach Meko: "). Don't silently fall back to the default datapack — the user asked to see the list.
• Pin file write fails — surface the error and tell the user the pin did NOT take effect. Do not claim success on a failed write.
• Ambiguous substring — never auto-pick. Re-render the filtered subset with new numbers and re-prompt.
• Stale pin (the pinned datapack no longer exists) — when the hook re-injects, the block is just text; a Meko call with the stale datapack_id will fail with a server error. Tell the user: "That pin is stale. Run meko-select-datapack to pick a fresh one or clear to unset." Don't silently swallow it.
• No agent_id in the SessionStart block — the hook didn't run successfully. Don't compute a slug from cwd or guess; tell the user the hook is broken and the skill can't pin until it's fixed.

Critical: do NOT modify the watermark

The watermark file (<session-id>.watermark.json) holds the conversation_id and is owned by capture.js. Never write to it from this skill. The datapack pin lives in a separate file (pin-<slug>.json) so concurrent skill writes and hook reads never collide.

Reference sections