Go’s `golang.org/x/tools/go/analysis` documentation defines an interface for modular static analysis: analyzers inspect one Go package at a time, report diagnostics, and can exchange results through a common API. The framework is designed so the same analyzer can be incorporated into command-line tools such as `vet`, editors, IDEs, build systems, test frameworks, code-review tools, and larger batch pipelines.
The opening paragraph introduces Go’s package-analysis interface, so this official wordmark identifies the language whose analyzer ecosystem the article explains. Credit: pkg.go.dev.
An analyzer is represented by an `Analyzer` value that describes its name, documentation, flags, dependencies, fact types, and execution function. A driver receives a `Pass` for one package, supplies syntax and type information, runs required analyzers first, and exposes their results through `Pass.ResultOf`. The analyzer then reports source-positioned diagnostics through the pass. This separation lets tool authors choose which checks to run without rewriting each checker for a particular interface.
The framework’s central scalability idea is the `Fact`. A fact is an intermediate result that is not necessarily useful to a developer on its own but can help another analysis reach a conclusion. The documentation gives the `printf` checker as an example: it can identify a function as a `printf` wrapper, export that fact, and allow later package analyses to apply stricter checks to calls that delegate through the wrapper.
Facts can be associated with a named object or with an entire package. Drivers are responsible for generating facts for dependencies and propagating them across package boundaries, including across separate processes. Because facts may be stored in build outputs, the API requires deterministic gob serialization; analyzer authors are also advised to keep facts stateless so content-addressable build caches do not suffer unnecessary misses.
The design deliberately leaves diagnostic severity out of the core `Diagnostic` type. The documentation says severity preferences differ among users and tools, so drivers should provide filtering and prioritization based on the producing analyzer and its optional category. That choice keeps the analyzer interface relatively small, but it also means a checker’s output is not automatically a ranked list of defects.
There are practical boundaries. Some driver implementations, including Bazel- and Blaze-based drivers described by the documentation, do not currently analyze packages in Go’s standard library. The `printf` checker therefore includes a built-in fact for `log.Printf` so it can still check calls when the standard-library package was not analyzed. This is an explicit workaround, not evidence that every driver provides identical package coverage.
The documentation also distinguishes analyzers that inspect typed syntax trees from those that read raw source or non-Go files. Examples such as `asmdecl` and `buildtag` show that the framework can reach beyond ordinary type information, but the analyzer author remains responsible for defining what the checker examines and how it reports findings. The API supplies a contract; it does not guarantee that every possible program property can be inferred soundly.
For testing, the `analysistest` subpackage runs an analyzer against fixture packages and checks expected diagnostics and facts using `// want` comments. For standalone use, `singlechecker` and `multichecker` provide entry points for one analyzer or a suite. These facilities make the framework usable beyond a single internal tool, although they do not remove the need to validate an analyzer’s assumptions and dependency graph.
The broader relevance is composability. Teams can add a checker to an existing driver by adding its analyzer to a list, while tool builders can reuse analyzers across different environments. The evidence establishes the documented interface, examples, and stated driver responsibilities; it does not establish adoption rates, performance benchmarks, or that every Go tooling ecosystem implements the framework in the same way.