> ## Documentation Index > Fetch the complete documentation index at: https://docs.tracks.alpic.ai/llms.txt > Use this file to discover all available pages before exploring further. # Launch an experiment > Starts an execution of the experiment as it is now: a run for every scenario, variant, agent and repetition, at most 500, started in the background. Each run is judged on its scenario's evaluations once it ends. Executions start only while your organization's balance is above $0. ## OpenAPI ````yaml https://tracks.alpic.ai/api/openapi.json post /experiments/{id}/executions openapi: 3.1.0 info: title: Tracks API version: 0.0.1 description: >- Run coding agents such as Claude Code in isolated sandboxes with an API key of your organization. Create a run with a prompt, then follow its output and what it costs, or launch an experiment to compare agents on your scenarios. servers: - url: https://tracks.alpic.ai/api security: [] tags: - name: Runs description: Start coding agents and follow their work. - name: Files description: Upload files to place in a run's sandbox. - name: Connections description: >- Let agents use MCP servers as one of their users, without their credentials entering the sandbox. - name: Experiments description: >- Define scenarios to give several agents in several variants, judged on what they did. - name: Executions description: Launch experiments and read their results. - name: Library description: What your experiments can give their agents. - name: System paths: /experiments/{id}/executions: post: tags: - Executions summary: Launch an experiment description: >- Starts an execution of the experiment as it is now: a run for every scenario, variant, agent and repetition, at most 500, started in the background. Each run is judged on its scenario's evaluations once it ends. Executions start only while your organization's balance is above $0. operationId: executions.launch parameters: - name: id in: path schema: $ref: '#/components/schemas/ExperimentId' required: true responses: '201': description: >- One launch of an experiment: a run for every scenario, variant, agent and repetition, with the experiment as it was when launched. content: application/json: schema: $ref: '#/components/schemas/Execution' '400': description: >- The request is invalid: a value is missing, has the wrong type or is out of range. Fix it before sending the request again. content: application/json: schema: $ref: '#/components/schemas/InvalidRequestEncoded' '401': description: >- The API key is missing, malformed or revoked, or its organization is closed. content: application/json: schema: $ref: '#/components/schemas/ApiKeyRefusedEncoded' '402': description: >- Your organization's balance is $0 or below: add funds to start runs again. content: application/json: schema: $ref: '#/components/schemas/InsufficientBalanceEncoded' '403': description: >- Your organization cannot start runs after a dispute on one of its payments: contact us. content: application/json: schema: $ref: '#/components/schemas/OrganizationBlockedEncoded' '404': description: No experiment with this id exists in your organization. content: application/json: schema: $ref: '#/components/schemas/ExperimentNotFoundEncoded' '422': description: >- The experiment cannot be launched as it is: `missing` says what to fix. content: application/json: schema: $ref: '#/components/schemas/ExperimentIncompleteEncoded' security: - bearer: [] components: schemas: ExperimentId: type: string description: Unique identifier of the experiment. Execution: type: object properties: id: $ref: '#/components/schemas/ExecutionId' experiment_id: $ref: '#/components/schemas/ExperimentId' number: type: integer minimum: -9007199254740991 maximum: 9007199254740991 description: Its place among the experiment's executions, from 1. launched_at: type: string canceled_at: type: string pending: type: boolean description: >- Whether some of its runs have not ended yet or wait for their evaluation results. Its pass rate is final once it is `false`, canceled or not. slots: type: object properties: total: type: integer minimum: 0 maximum: 9007199254740991 description: Runs the execution plans. running: type: integer minimum: 0 maximum: 9007199254740991 description: Runs not started yet or not ended. judging: type: integer minimum: 0 maximum: 9007199254740991 description: Ended runs waiting for their evaluation results. judged: type: integer minimum: 0 maximum: 9007199254740991 description: Runs with a verdict. passed: type: integer minimum: 0 maximum: 9007199254740991 description: Runs that passed their scenario. required: - total - running - judging - judged - passed additionalProperties: false description: >- How many of its slots, one per scenario, variant, agent and repetition, stand where. pass_rate: type: integer minimum: 0 maximum: 100 description: >- Runs that passed out of those with a verdict, as a whole percent. Absent until one run has a verdict. cost_usd: anyOf: - type: number - type: string enum: - Infinity - '-Infinity' - NaN required: - id - experiment_id - number - launched_at - pending - slots - cost_usd additionalProperties: false description: >- One launch of an experiment: a run for every scenario, variant, agent and repetition, with the experiment as it was when launched. InvalidRequestEncoded: type: object properties: _tag: type: string enum: - InvalidRequest message: type: string description: Every problem found, in one sentence. location: type: string enum: - path - query - header - body description: The part of the request that is wrong. issues: type: array items: $ref: '#/components/schemas/RequestIssue' description: Each problem found, with where it is. required: - _tag - message - location - issues additionalProperties: false ApiKeyRefusedEncoded: type: object properties: _tag: type: string enum: - ApiKeyRefused message: type: string required: - _tag - message additionalProperties: false InsufficientBalanceEncoded: type: object properties: _tag: type: string enum: - InsufficientBalance message: type: string top_up_url: type: string description: Where to add funds to your organization's balance. required: - _tag - message - top_up_url additionalProperties: false OrganizationBlockedEncoded: type: object properties: _tag: type: string enum: - OrganizationBlocked message: type: string required: - _tag - message additionalProperties: false ExperimentNotFoundEncoded: type: object properties: _tag: type: string enum: - ExperimentNotFound message: type: string required: - _tag - message additionalProperties: false ExperimentIncompleteEncoded: type: object properties: _tag: type: string enum: - ExperimentIncomplete message: type: string missing: type: array items: type: string description: Each thing to fix before launching, in a sentence. required: - _tag - message - missing additionalProperties: false ExecutionId: type: string description: Unique identifier of the execution. RequestIssue: type: object properties: path: type: array items: anyOf: - type: string - type: number - type: string enum: - Infinity - '-Infinity' - NaN description: >- Keys leading to the wrong value inside that part of the request, such as `["agent", "model"]`. Empty when the problem concerns that part as a whole. message: type: string description: What is wrong with the value. required: - path - message additionalProperties: false description: One problem found in the request. securitySchemes: bearer: description: >- An API key of your organization, starting with `trk_`, sent as `Authorization: Bearer `. type: http scheme: bearer ```` This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.