Working with the Salt & Solvate Library

Beta: every salt and solvent endpoint needs EARLY-ACCESS: true.

The library holds the salt and solvent counterparts that Forms reference (see the concept model). It’s a tenant-wide, admin-managed catalog: you populate it once, and Forms then point at its entries by structure.

The app shows one merged “Salt & Solvate” library; the API exposes two separate resources. In the Benchling app the library is a single flat list with no salt-vs-solvate distinction. On the API, salts and solvents are distinct resources: /salt (IDs slt_...) and /solvent (IDs slvt_...), each with its own endpoints. Note that the API noun is solvent, while the product term is “Solvate”.

Endpoints

Salts and solvents mirror each other exactly. Swap salt/slt_ for solvent/slvt_:

Operation	Salt endpoint	Solvent endpoint
Create one	`POST /salt`	`POST /solvent`
Get one	`GET /salt/{salt_id}`	`GET /solvent/{solvent_id}`
List	`GET /salt/items`	`GET /solvent/items`
Update / archive	`PATCH /salt/{salt_id}`	`PATCH /solvent/{solvent_id}`
Create a handful (up to 4)	`POST /salt:batch-create`	`POST /solvent:batch-create`
Create many (async)	`POST /salt:bulk-create`	`POST /solvent:bulk-create`

:batch-update and :bulk-update also exist for both. The bulk endpoints follow the same file-based flow as bulk molecule creation.

Fields

A salt or solvent is a small object: a name, a structure, and an optional code.

Field	Notes
`name`	Required. Unique (case-insensitive) within its own library. A solvent may reuse a salt’s name.
`smiles`	Required. SMILES of the neutral form; the canonical SMILES and molecular formula are derived from it. Immutable after creation.
`code`	Optional short identifier (for example, `"HCl"`). Unique (case-insensitive) *across all salts and* solvents** in the tenant.

A minimal create body is just { "name": "Hydrochloride", "smiles": "Cl", "code": "HCl" }, sent with the standard auth and the EARLY-ACCESS: true header (see Getting started).

Update is limited to name, code, and archive state. The structure can’t change. To “edit” a structure, archive the entry and create a new one.

Limits and rules

Tenant admin permissions are required to create or update entries.
The combined salt and solvent library is capped at 2000 non-archived entries, and each structure is limited to 50 atoms.
Within a library, each structure may appear only once. A solvent may reuse a salt’s structure, and vice versa.
Archived entries still reserve their name and structure. If a match is archived, unarchive it; you can’t recreate it.