Linear

Linear is one of the six sources with both an open-source ingest skill and a paid webhook receiver.

Open-source ingest skill

Pull issues and project status from a Linear team or project into External Inputs/Linear/<team>/<YYYY-MM-DD>.md. Requires a Linear API key.

/ingest-linear mycelium --days 7

Real-time push from Linear webhooks.

POST /webhooks/linear/{tenant_id}

Signature: Linear signs every payload with X-Linear-Signature. The receiver validates the HMAC-SHA256 signature.

In Linear, go to Settings > API > Webhooks > Create webhook.
Set URL to https://runtime.myceliumai.co/webhooks/linear/{your_tenant_id}.
Select resources: Issues, Projects, Cycles, Comments (recommended).
Copy the signing key and add it to the runtime: LINEAR_WEBHOOK_SECRET_{TENANT_ID} in your env.

Linear event	Memory category	Notes
Issue created	exception	New issue = unresolved exception
Issue status change	exception	Completed = resolved; cancelled = closed
Project update	decision	Status changes, milestone moves
Cycle completed	decision	Sprint retrospective data

Failed deliveries land in the per-tenant dead-letter folder. Replay via:

POST /admin/webhooks/replay/{tenant_id}/{event_id}