---
title: "Add sequences to experiment"
method: POST
path: "/api/v1/sequences"
tags: ["sequences"]
---

# Add sequences to experiment

`POST /api/v1/sequences`

## Request

- Base URL: `https://devs.adaptyvbio.com`
- URL: `https://devs.adaptyvbio.com/api/v1/sequences`
- Auth: HTTP bearer

Appends sequences to a draft experiment identified by its human-readable code
(e.g., "PROJ-001"). The experiment must be in Draft status; confirmed or later-stage
experiments cannot accept new sequences. Create a new experiment to submit
additional sequences if the original has progressed past draft.

## Request body

- SequenceAddRequest: Request body for adding sequences to a draft experiment. Identifies the target experiment by its human-readable code (e.g., "PROJ-001") rather than UUID. The experiment must be in Draft status; appending sequences to confirmed experiments returns 409 Conflict.
  - `experiment_code` string, required: Human-readable experiment code (e.g., "PROJ-001")
  - `sequences` SequenceEntry[], required: Sequences to append to the experiment
    - `aa_string` string, required: A validated amino acid sequence string. Contains only the 20 natural amino acids (single-letter codes: A, C, D, E, F, G, H, I, K, L, M, N, P, Q, R, S, T, V, W, Y) and colons for multichain notation. Input is case-insensitive; stored uppercase. Multichain sequences use colon separators (e.g., `MVLS:EVQL` for a two-chain construct). Invalid characters or empty strings are rejected.
    - `control` boolean: Whether the sequence should be treated as a control well
    - `metadata` unknown
    - `name` string, nullable: Optional name for the sequence (e.g., "mAb1", "scFv-001")

## Response `201`

Sequences added

- SequenceAddResponse: Response after successfully adding sequences to an experiment.
  - `added_count` integer, required: Number of sequences added
  - `experiment_code` string, required: Human-readable experiment code
  - `experiment_id` string, uuid, required: UUID of the experiment
  - `sequence_ids` string[], required: UUIDs of the newly created sequences

## Other responses

- `400`: Invalid request: empty sequences array, malformed data, or a duplicate sequence — two sequences sharing normalized residues and tag location, either within this request or against one already stored on the experiment (Fabs exempt)
- `404`: Experiment not found or access denied
- `409`: Experiment is not in Draft status
- `500`: Internal server error

---

[API](https://skmtc.dev/adaptyvbio/apis/adaptyv-foundry-api.md) - [All operations](https://skmtc.dev/adaptyvbio/apis/adaptyv-foundry-api/llms.txt) - [OpenAPI document](https://skmtc.dev/adaptyvbio/apis/adaptyv-foundry-api/revisions/5a2228f4bd59?raw)