---
title: "Library Acquire"
method: POST
path: "/library/acquire/{cid}"
---

# Library Acquire

`POST /library/acquire/{cid}`

## Request

- Base URL: `https://api-docs.session-exchange.com` (the document declares no server; this is the origin it was published from)
- URL: `https://api-docs.session-exchange.com/library/acquire/{cid}`
- Auth: none declared

Import a marketplace item you're ENTITLED to into your PRIVATE library as a launchable base
copy, tagged with where it came from (`acquired_from`). This is the bridge: a bought/imported
session lives in the SELLER'S tenant and isn't launchable via the library; acquiring stages a
private copy in YOUR personal tenant so `a4sx launch --a4sx-session` and the lineage tree
work on it normally.

Accepts a marketplace COLLECTION (its session member is copied) or a bare SESSION listing
(synthesised as a one-member collection below, so the copy, scrub and provenance are identical).
Reuses the same cross-tenant read + entitlement gate as GET /memory/collections/{cid}/bundle: the
entitlement check is MANDATORY (a paid item without entitlement → 402). Idempotent: re-acquiring
the same source stages a NEW VERSION of the same `col-lib-*` entry.

A collection with NO session member is reading material, not a base → 409 `memory_only` with
the two routes that DO serve it (never a silent no-op: the Library lists only what lands here).

The copy carries a private `acquired_from` provenance field only — NOT a royalty edge. Publishing a
derivative for cross-author credit is the separate, author-gated marketplace `builds_on` declaration.
AUTH: your `ge_sess_` session bearer (a human account — the copy lands in your personal library).

## Path parameters

- `cid` string, required

## Query parameters

- `version` string
- `tenant` string

## Response `200`

Successful Response

- unknown

## Other responses

- `422`: Validation Error

---

[API](https://skmtc.dev/session-exchange/apis/a4sx.md) · [All operations](https://skmtc.dev/session-exchange/apis/a4sx/llms.txt) · [OpenAPI document](https://skmtc.dev/session-exchange/apis/a4sx/revisions/abaefc33dfc7?raw)