> ## Documentation Index > Fetch the complete documentation index at: https://docs.cdp.coinbase.com/llms.txt > Use this file to discover all available pages before exploring further. # Get Public Product Book > Get a list of bids/asks for a single product. The amount of detail shown can be customized with the limit parameter. ## OpenAPI ````yaml GET /api/v3/brokerage/market/product_book openapi: 3.0.0 info: title: Coinbase Advanced Trade API version: '0.1' servers: - url: https://api.coinbase.com security: - apiKeyAuth: [] paths: /api/v3/brokerage/market/product_book: get: tags: - Public summary: Get Public Product Book description: >- Get a list of bids/asks for a single product. The amount of detail shown can be customized with the limit parameter. operationId: RetailBrokerageApi_GetPublicProductBook parameters: - name: product_id description: The trading pair (e.g. 'BTC-USD'). in: query required: true schema: type: string - name: limit description: 'The number of bid/asks to be returned. ' in: query required: false schema: type: integer format: int32 - name: aggregation_price_increment description: >- The minimum price intervals at which buy and sell orders are grouped or combined in the order book. in: query required: false schema: type: string responses: '200': description: A successful response. content: application/json: schema: $ref: >- #/components/schemas/coinbase.public_api.authed.retail_brokerage_api.GetProductBookResponse text/event-stream: schema: $ref: >- #/components/schemas/coinbase.public_api.authed.retail_brokerage_api.GetProductBookResponse default: description: An unexpected error response. content: application/json: schema: $ref: '#/components/schemas/grpc.gateway.runtime.Error' text/event-stream: schema: $ref: '#/components/schemas/grpc.gateway.runtime.Error' components: schemas: coinbase.public_api.authed.retail_brokerage_api.GetProductBookResponse: type: object properties: pricebook: required: - pricebook allOf: - $ref: >- #/components/schemas/coinbase.public_api.authed.retail_brokerage_api.PriceBook last: type: string mid_market: type: string spread_bps: type: string spread_absolute: type: string required: - pricebook grpc.gateway.runtime.Error: type: object properties: error: type: string code: type: integer format: int32 message: type: string details: type: array items: $ref: '#/components/schemas/google.protobuf.Any' coinbase.public_api.authed.retail_brokerage_api.PriceBook: type: object properties: product_id: type: string example: BTC-USD description: The trading pair (e.g. 'BTC-USD'). required: - product_id bids: type: array items: $ref: >- #/components/schemas/coinbase.public_api.authed.retail_brokerage_api.L2Level required: - bids asks: type: array items: $ref: >- #/components/schemas/coinbase.public_api.authed.retail_brokerage_api.L2Level required: - asks time: type: string format: RFC3339 Timestamp required: - product_id - bids - asks google.protobuf.Any: type: object properties: type_url: type: string description: >- A URL/resource name that uniquely identifies the type of the serialized protocol buffer message. This string must contain at least one "/" character. The last segment of the URL's path must represent the fully qualified name of the type (as in `path/google.protobuf.Duration`). The name should be in a canonical form (e.g., leading "." is not accepted). In practice, teams usually precompile into the binary all types that they expect it to use in the context of Any. However, for URLs which use the scheme `http`, `https`, or no scheme, one can optionally set up a type server that maps type URLs to message definitions as follows: * If no scheme is provided, `https` is assumed. * An HTTP GET on the URL must yield a [google.protobuf.Type][] value in binary format, or produce an error. * Applications are allowed to cache lookup results based on the URL, or have them precompiled into a binary to avoid any lookup. Therefore, binary compatibility needs to be preserved on changes to types. (Use versioned type names to manage breaking changes.) Note: this functionality is not currently available in the official protobuf release, and it is not used for type URLs beginning with type.googleapis.com. As of May 2023, there are no widely used type server implementations and no plans to implement one. Schemes other than `http`, `https` (or the empty scheme) might be used with implementation specific semantics. value: type: string format: byte description: >- Must be a valid serialized protocol buffer of the above specified type. description: >- `Any` contains an arbitrary serialized protocol buffer message along with a URL that describes the type of the serialized message. Protobuf library provides support to pack/unpack Any values in the form of utility functions or additional generated methods of the Any type. Example 1: Pack and unpack a message in C++. Foo foo = ...; Any any; any.PackFrom(foo); ... if (any.UnpackTo(&foo)) { ... } Example 2: Pack and unpack a message in Java. Foo foo = ...; Any any = Any.pack(foo); ... if (any.is(Foo.class)) { foo = any.unpack(Foo.class); } // or ... if (any.isSameTypeAs(Foo.getDefaultInstance())) { foo = any.unpack(Foo.getDefaultInstance()); } Example 3: Pack and unpack a message in Python. foo = Foo(...) any = Any() any.Pack(foo) ... if any.Is(Foo.DESCRIPTOR): any.Unpack(foo) ... Example 4: Pack and unpack a message in Go foo := &pb.Foo{...} any, err := anypb.New(foo) if err != nil { ... } ... foo := &pb.Foo{} if err := any.UnmarshalTo(foo); err != nil { ... } The pack methods provided by protobuf library will by default use 'type.googleapis.com/full.type.name' as the type URL and the unpack methods only use the fully qualified type name after the last '/' in the type URL, for example "foo.bar.com/x/y.z" will yield type name "y.z". JSON ==== The JSON representation of an `Any` value uses the regular representation of the deserialized, embedded message, with an additional field `@type` which contains the type URL. Example: package google.profile; message Person { string first_name = 1; string last_name = 2; } { "@type": "type.googleapis.com/google.profile.Person", "firstName": , "lastName": } If the embedded message type is well-known and has a custom JSON representation, that representation will be embedded adding a field `value` which holds the custom JSON in addition to the `@type` field. Example (for message [google.protobuf.Duration][]): { "@type": "type.googleapis.com/google.protobuf.Duration", "value": "1.212s" } coinbase.public_api.authed.retail_brokerage_api.L2Level: type: object properties: price: type: string size: type: string securitySchemes: apiKeyAuth: type: http scheme: bearer bearerFormat: JWT description: >- A JWT signed using your CDP API Key Secret, encoded in base64. Refer to the [Creating API Keys](/coinbase-app/authentication-authorization/api-key-authentication) section of our Coinbase App Authentication docs for information on how to generate your Bearer Token. ````