API Documentation

Pkgsite provides a JSON API for accessing information about Go packages and modules.

Requests

All requests are GET requests whose first URL segment selects the request type. Except for search, the remaining segments specify a module or package path. Additional arguments are specified as query parameters.

Package paths are ambiguous: the same path a/b/c could be package c in module a/b or package b/c in module a. If both exist, the API returns an error with a list of possible modules in its candidates field. Make a follow-up request with the module query parameter to disambiguate. (Note: this behavior differs from the pkgsite UI, which selects the longest matching module path.)

Some routes accept an optional version query parameter. If missing, the latest version is chosen.

Some routes accept optional GOOS and GOARCH query parameters to select the desired build context of the documentation. If omitted, the default documentation build context is selected, typically linux/amd64.

Some routes accept a filter. Only items that match the filter are returned. The filter must be a Go expression that returns a boolean value. Filters support the following subset of Go:

• The values true, false and nil.
• == and != on any value.
• +, -,*, / and % on integers.
• + on strings.
• <, <=, > and >= on strings and integers.
• The following functions:

  contains(s, sub)

  String s contains substring sub.

  hasPrefix(s, pre)

  String s has the prefix pre.

  hasSuffix(s, suf)

  String s has the suffix suf.

  matches(s, re)

  String s matches the regular expression re.

In addition, each route adds its own variables for the list items being filtered. In general, each JSON field is a variable.

Most filters will need to be percent-encoded. Go programs should call url.QueryEscape to encode filters and all other query parameter values. Or better, put all values into a url.Values and then call Encode on that.

Responses

All routes return a JSON response. You can find a link to the corresponding Go type for a route in the documentation below. Errors are also returned as a JSON object, whose message field contains the error message.

You can access the machine-readable OpenAPI Specification.

Pagination

Some responses are paginated. Each response page has a nextPageToken, which is non-empty if there is another page of items. To retrieve the next page, repeat the original request verbatim, adding a token query parameter whose value is the next-page token from the response. Changing the request in any way other than providing a token may result in an error.

As long as nextPageToken is non-empty, there is another page, even if the current page has no items.

Routes

• /v1beta/package/{path}

  Information about the package at {path}.

  Parameters:

  Name	Type	Description
  module	string	Module path.
  version	string	Module version: semantic version, 'latest', or default branches 'master' or 'main'. (Latest if empty).
  goos	string	GOOS of documentation build context.
  goarch	string	GOARCH of documentation build context.
  doc	string	Documentation format: text, html, md or markdown. If omitted, documentation is not returned.
  examples	bool	Whether to include examples with the returned documentation.
  imports	bool	Whether to include the packages that this one imports.
  licenses	bool	Whether to include licenses in the result.

  Response: Package

  Example Request

  curl -L https://pkg.go.dev/v1beta/package/golang.org/x/time/rate

  Example Response

  {
    "modulePath": "golang.org/x/time",
    "version": "v0.15.0",
    "isLatest": true,
    "isStandardLibrary": false,
    "goos": "all",
    "goarch": "all",
    "path": "golang.org/x/time/rate",
    "name": "rate",
    "synopsis": "Package rate provides a rate limiter.",
    "isRedistributable": true
  }
  

• /v1beta/module/{path}

  Information about the module at {path}.

  Parameters:

  Name	Type	Description
  version	string	Module version: semantic version, 'latest', or default branches 'master' or 'main'. (Latest if empty).
  licenses	bool	Whether to include licenses in the result.
  readme	bool	Whether to include the README in the result.

  Response: Module

  Example Request

  curl -L https://pkg.go.dev/v1beta/module/golang.org/x/time

  Example Response

  {
    "path": "golang.org/x/time",
    "version": "v0.15.0",
    "commitTime": "2026-02-11T19:14:29Z",
    "isLatest": true,
    "isRedistributable": true,
    "isStandardLibrary": false,
    "hasGoMod": true,
    "repoUrl": "https://cs.opensource.google/go/x/time"
  }
  

• /v1beta/versions/{path}

  Versions of the module at {path}. If there are tagged versions, they are returned. Otherwise, the 10 most recent pseudo-versions are returned. The versions are in descending order. Only results that match the filter query parameter are returned.

  Parameters:

  Name	Type	Description
  limit	int	Max number of items to return.
  token	string	Where to resume listing.
  filter	string	Include only items matching the regular expression filter.

  Response: PaginatedResponse[ModuleVersion]

  Example Request

  curl -L https://pkg.go.dev/v1beta/versions/golang.org/x/time?limit=3

  Example Response

  {
    "items": [
      {
        "modulePath": "golang.org/x/time",
        "version": "v0.15.0",
        "commitTime": "2026-02-11T19:14:29Z",
        "isRedistributable": true,
        "hasGoMod": true,
        "latestVersion": "v0.15.0",
        "deprecated": false,
        "deprecationReason": "",
        "retracted": false,
        "retractionReason": ""
      },
      {
        "modulePath": "golang.org/x/time",
        "version": "v0.14.0",
        "commitTime": "2025-09-16T23:29:52Z",
        "isRedistributable": true,
        "hasGoMod": true,
        "latestVersion": "v0.15.0",
        "deprecated": false,
        "deprecationReason": "",
        "retracted": false,
        "retractionReason": ""
      },
      {
        "modulePath": "golang.org/x/time",
        "version": "v0.13.0",
        "commitTime": "2025-08-13T14:44:00Z",
        "isRedistributable": true,
        "hasGoMod": true,
        "latestVersion": "v0.15.0",
        "deprecated": false,
        "deprecationReason": "",
        "retracted": false,
        "retractionReason": ""
      }
    ],
    "total": 15,
    "nextPageToken": "3e762760ded3055048473332e4bd6fa1"
  }
  

• /v1beta/packages/{path}

  Information about packages of the module at {path}. Filtering is applied to the list of packages in the response. Only packages that match the filter query parameter are returned.

  Parameters:

  Name	Type	Description
  version	string	Module version: semantic version, 'latest', or default branches 'master' or 'main'. (Latest if empty).
  limit	int	Max number of items to return.
  token	string	Where to resume listing.
  filter	string	Include only items matching the regular expression filter.

  Response: PackagesResponse

  Example Request

  curl -L https://pkg.go.dev/v1beta/packages/golang.org/x/time/rate

  Example Response

  {
    "code": 400,
    "message": "golang.org/x/time/rate is a package, not a module",
    "fixes": [
      "retry the call with the containing module: \"golang.org/x/time\""
    ]
  }
  

• /v1beta/search

  Search results. Only results that match the filter query parameter are returned. Results are sorted by how well the match the query, with the best match first.

  Parameters:

  Name	Type	Description
  q	string	Find packages matching this query.
  symbol	string	If non-empty, find symbols matching this string. The query further restricts the search to matching packages.
  limit	int	Max number of items to return.
  token	string	Where to resume listing.
  filter	string	Include only items matching the regular expression filter.

  Response: PaginatedResponse[SearchResult]

  Example Request

  curl -L https://pkg.go.dev/v1beta/search?q=xyzzy

  Example Response

  {
    "items": [
      {
        "packagePath": "github.com/docktermj/go-xyzzy-helpers/logger",
        "modulePath": "github.com/docktermj/go-xyzzy-helpers",
        "version": "v0.2.2",
        "synopsis": "Package helper ..."
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-helpers/g2configuration",
        "modulePath": "github.com/docktermj/go-xyzzy-helpers",
        "version": "v0.2.2",
        "synopsis": "Package helper ..."
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-grpc/g2diagnostic",
        "modulePath": "github.com/docktermj/go-xyzzy-grpc",
        "version": "v0.0.0-20221028160434-9c34bd3a1481",
        "synopsis": ""
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-helpers/logmessage",
        "modulePath": "github.com/docktermj/go-xyzzy-helpers",
        "version": "v0.2.2",
        "synopsis": "Package message ..."
      },
      {
        "packagePath": "github.com/wade-rees-me/striker-go/cmd/striker/xyzzy",
        "modulePath": "github.com/wade-rees-me/striker-go",
        "version": "v1.0.3",
        "synopsis": ""
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-grpc/g2diagnosticclient",
        "modulePath": "github.com/docktermj/go-xyzzy-grpc",
        "version": "v0.0.0-20221028160434-9c34bd3a1481",
        "synopsis": "Package main implements a client for the service."
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-grpc/g2diagnosticclientcli",
        "modulePath": "github.com/docktermj/go-xyzzy-grpc",
        "version": "v0.0.0-20221028160434-9c34bd3a1481",
        "synopsis": "Package main implements a client for the service."
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-grpc/g2diagnosticserver",
        "modulePath": "github.com/docktermj/go-xyzzy-grpc",
        "version": "v0.0.0-20221028160434-9c34bd3a1481",
        "synopsis": ""
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-grpc/g2diagnosticservercli",
        "modulePath": "github.com/docktermj/go-xyzzy-grpc",
        "version": "v0.0.0-20221028160434-9c34bd3a1481",
        "synopsis": ""
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-helpers",
        "modulePath": "github.com/docktermj/go-xyzzy-helpers",
        "version": "v0.2.2",
        "synopsis": ""
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-grpc/v2/g2diagnostic",
        "modulePath": "github.com/docktermj/go-xyzzy-grpc/v2",
        "version": "v2.0.0-20220622205531-7c693c6f8eb1",
        "synopsis": ""
      },
      {
        "packagePath": "github.com/docktermj/go-xyzzy-grpc/v2/server",
        "modulePath": "github.com/docktermj/go-xyzzy-grpc/v2",
        "version": "v2.0.0-20220622205531-7c693c6f8eb1",
        "synopsis": ""
      },
      {
        "packagePath": "github.com/blasphemy/xyzzy2/lib/xyzzy",
        "modulePath": "github.com/blasphemy/xyzzy2",
        "version": "v0.0.0-20141223201256-7f5f89b3fd2e",
        "synopsis": ""
      }
    ],
    "total": 13
  }
  

• /v1beta/symbols/{path}

  List of symbols for the package at {path}. Filtering is applied to the list of symbols in the response. Only symbols that match the filter query parameter are returned.

  Parameters:

  Name	Type	Description
  module	string	Module path.
  version	string	Module version: semantic version, 'latest', or default branches 'master' or 'main'. (Latest if empty).
  goos	string	GOOS of documentation build context.
  goarch	string	GOARCH of documentation build context.
  limit	int	Max number of items to return.
  token	string	Where to resume listing.
  filter	string	Include only items matching the regular expression filter.

  Response: PackageSymbols

  Example Request

  curl -L https://pkg.go.dev/v1beta/symbols/golang.org/x/time/rate

  Example Response

  {
    "modulePath": "golang.org/x/time",
    "version": "v0.15.0",
    "symbols": {
      "items": [
        {
          "name": "Limit",
          "kind": "Type",
          "synopsis": "type Limit float64",
          "parent": "Limit"
        },
        {
          "name": "Every",
          "kind": "Function",
          "synopsis": "func Every(interval time.Duration) Limit",
          "parent": "Limit"
        },
        {
          "name": "Limiter",
          "kind": "Type",
          "synopsis": "type Limiter struct{}",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.Allow",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) Allow() bool",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.AllowN",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) AllowN(t time.Time, n int) bool",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.Burst",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) Burst() int",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.Limit",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) Limit() Limit",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.Reserve",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) Reserve() *Reservation",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.ReserveN",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) ReserveN(t time.Time, n int) *Reservation",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.SetBurst",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) SetBurst(newBurst int)",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.SetBurstAt",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) SetBurstAt(t time.Time, newBurst int)",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.SetLimit",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) SetLimit(newLimit Limit)",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.SetLimitAt",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) SetLimitAt(t time.Time, newLimit Limit)",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.Tokens",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) Tokens() float64",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.TokensAt",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) TokensAt(t time.Time) float64",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.Wait",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) Wait(ctx context.Context) (err error)",
          "parent": "Limiter"
        },
        {
          "name": "Limiter.WaitN",
          "kind": "Method",
          "synopsis": "func (lim *Limiter) WaitN(ctx context.Context, n int) (err error)",
          "parent": "Limiter"
        },
        {
          "name": "NewLimiter",
          "kind": "Function",
          "synopsis": "func NewLimiter(r Limit, b int) *Limiter",
          "parent": "Limiter"
        },
        {
          "name": "Reservation",
          "kind": "Type",
          "synopsis": "type Reservation struct{}",
          "parent": "Reservation"
        },
        {
          "name": "Reservation.Cancel",
          "kind": "Method",
          "synopsis": "func (r *Reservation) Cancel()",
          "parent": "Reservation"
        },
        {
          "name": "Reservation.CancelAt",
          "kind": "Method",
          "synopsis": "func (r *Reservation) CancelAt(t time.Time)",
          "parent": "Reservation"
        },
        {
          "name": "Reservation.Delay",
          "kind": "Method",
          "synopsis": "func (r *Reservation) Delay() time.Duration",
          "parent": "Reservation"
        },
        {
          "name": "Reservation.DelayFrom",
          "kind": "Method",
          "synopsis": "func (r *Reservation) DelayFrom(t time.Time) time.Duration",
          "parent": "Reservation"
        },
        {
          "name": "Reservation.OK",
          "kind": "Method",
          "synopsis": "func (r *Reservation) OK() bool",
          "parent": "Reservation"
        },
        {
          "name": "Sometimes",
          "kind": "Type",
          "synopsis": "type Sometimes struct{ ... }",
          "parent": "Sometimes"
        },
        {
          "name": "Sometimes.Do",
          "kind": "Method",
          "synopsis": "func (s *Sometimes) Do(f func())",
          "parent": "Sometimes"
        },
        {
          "name": "Sometimes.Every",
          "kind": "Field",
          "synopsis": "Every int",
          "parent": "Sometimes"
        },
        {
          "name": "Sometimes.First",
          "kind": "Field",
          "synopsis": "First int",
          "parent": "Sometimes"
        },
        {
          "name": "Sometimes.Interval",
          "kind": "Field",
          "synopsis": "Interval time.Duration",
          "parent": "Sometimes"
        },
        {
          "name": "Inf",
          "kind": "Constant",
          "synopsis": "const Inf",
          "parent": "Inf"
        },
        {
          "name": "InfDuration",
          "kind": "Constant",
          "synopsis": "const InfDuration",
          "parent": "InfDuration"
        }
      ],
      "total": 31
    }
  }
  

• /v1beta/imported-by/{path}

  Paths of packages importing the package at {path}, not including packages in the same module. Filtering is applied to the list of paths in the response. Only paths that match the filter query parameter are returned. Within a filter, the variable `path` is set to the import path.

  Parameters:

  Name	Type	Description
  module	string	Module path.
  version	string	Module version: semantic version, 'latest', or default branches 'master' or 'main'. (Latest if empty).
  limit	int	Max number of items to return.
  token	string	Where to resume listing.
  filter	string	Include only items matching the regular expression filter.

  Response: PackageImportedBy

  Example Request

  curl -L https://pkg.go.dev/v1beta/imported-by/golang.org/x/time/rate?limit=10&filter=%5E.%2A%5C.io%2F

  Example Response

  {
    "code": 400,
    "message": "parsing filter \"^.*\\.io/\": 1:2: expected operand, found '.' (and 1 more errors)",
    "fixes": [
      "the 'filter' query parameter must be a valid Go expression; see the documentation at /v1beta/api"
    ]
  }
  

• /v1beta/vulns/{path}

  Vulnerabilities of the module or package at {path}, from the Go vulnerability database (https://vuln.go.dev). Only results that match the filter query parameter are returned.

  Parameters:

  Name	Type	Description
  module	string	Module path.
  version	string	Module version: semantic version, 'latest', or default branches 'master' or 'main'. (Latest if empty).
  limit	int	Max number of items to return.
  token	string	Where to resume listing.
  filter	string	Include only items matching the regular expression filter.

  Response: PaginatedResponse[Vulnerability]

  Example Request

  curl -L https://pkg.go.dev/v1beta/vulns/golang.org/x/image

  Example Response

  {
    "items": null,
    "total": 0
  }