How do I stop an AI agent from hallucinating a REST API in my Go client?

Make it fetch the page. Atlas calls websearch to locate the current documentation and webfetch to pull it into context with format markdown or text, then writes the Go struct tags from the real payload and verifies them with table-driven go test cases.

Does Atlas upload my Go code when it fetches API documentation?

No. webfetch pulls a URL into context and nothing more. The permission prompt shows the URL as the pattern before any request goes out, and every Atlas tool call is permission-gated against allow, ask, and deny rules, so context cannot be quietly exfiltrated to arbitrary hosts.

Why do wrong JSON struct tags in Go fail silently?

Because encoding/json simply leaves the field at its zero value when the key is absent. Nothing errors. Writing the tag from the fetched documentation rather than from memory is the only reliable defense, which is why Atlas researches the API before writing the client.

Will Atlas match my module's existing error handling in a new client package?

Yes, if you let it grep first. Atlas checks the repo's own conventions with grep before committing to a pattern, so the new client wraps errors and threads context.Context the way the rest of your Go packages already do.

Does Atlas update go.mod and go.sum for a new dependency?

Atlas adds dependencies through go mod so go.sum stays consistent with your module. The command runs through a permission-gated bash call, and Atlas surfaces a unified diff for every file edit before writing.

How should I test a Go API client that Atlas generated?

With table-driven tests run by go test, one row per documented response body including the error codes the reference lists. Ask Atlas to build the table from the fetched samples so the field names come from the vendor rather than from the model.

When does Atlas use websearch instead of searching my repository?

Only when the answer is not in the repository. Questions about your own Go packages go to codebase_search, grep, and the lsp tool. Questions about a vendor's current endpoint shape go to websearch and webfetch, once, behind an explicit permission prompt.

Research a Third-Party API Before Integrating It in Go with Atlas (2026)

Atlas researches a third-party API before you write the Go integration by leaving the module when the answer is not in the module. websearch finds the current documentation page, and its description carries the current year so the model biases toward fresh sources. webfetch pulls the page down with format markdown or text, and the permission prompt shows the URL as the pattern before any request goes out. With the real request and response shapes in context, Atlas writes the client package with correct struct tags and error handling, greps your module to match existing conventions, and proves the result with go test.

How do you stop a Go API client from being written against a guessed payload?

Fetch the documentation instead of trusting recall. Atlas calls websearch, whose description injects the current year so the model biases toward 2026 sources, then webfetch to pull the page. The struct tags Atlas then writes in your Go client carry the field names the API actually returns.

Go's encoding/json will not save you here, and that is the trap. If the documentation says the field is expires_at and the model writes ExpiresAt string with a struct tag of json:"expiry", nothing fails. The JSON decodes cleanly, the field is the zero value, and the bug surfaces weeks later as a token that never appears to expire. Go's type system has no opinion about a struct tag that points at a key nobody sends. The only defense is writing the tag from the real payload, which is exactly what fetching the page gives you. Atlas reads the response schema off the live reference, writes the struct with matching tags, and the first table-driven test that decodes a real sample either passes or tells you immediately.

What does webfetch send, and can it reach anything?

webfetch pulls exactly 1 URL and asks first. The webfetch permission prompt uses the URL as the pattern, so approval is per page or per host rather than blanket network access, and your Go source under internal/ is never uploaded. Every Atlas tool call is permission-gated against allow, ask, and deny rules before it runs.

An agent with unrestricted network access is a data-exfiltration risk regardless of how careful the model is, so Atlas puts webfetch and websearch behind explicit permissions and makes the URL visible in the prompt before any request goes out. In a Go repository the practical shape is: approve the vendor's documentation host, decline the rest, and get on with it. The format parameter is worth using deliberately. Passing format markdown or text steers the Accept header toward a compact representation, so a long API reference does not consume the context you still need for your own packages, your interfaces, and your go.mod dependency graph. Fetching is research, not integration: nothing about it modifies go.mod, go.sum, or a single .go file.

How does Atlas make a new Go client match my module's conventions?

Atlas greps the Go module before committing to a pattern. Every mature Go codebase has already decided how it wraps errors, whether it passes context.Context first, and how it names constructors, and a client package that ignores those 3 decisions will be rewritten by a reviewer within a day.

The documented workflow ends with grep for a reason. A model that has just read an API reference is full of the vendor's vocabulary and none of yours. Before the integration lands, grep the module for the existing error-wrapping idiom, for how other packages accept a context.Context, for the interface the rest of internal/ expects an outbound client to satisfy. Atlas indexes code by AST declarations using tree-sitter rather than blind line windows, so codebase_search surfaces those real declarations and not arbitrary chunks. The write and edit tools then produce the client package, and Atlas computes a unified diff for every file edit and surfaces it for approval before writing, so nothing appears under internal/ that you have not read. Run gofmt on the result.

How do you test a Go API client written from fetched docs?

Write table-driven tests against the payloads the documentation actually shows, then run go test. A table with one row per documented response, including the two error codes the reference lists, turns the fetched page into an executable contract instead of a paragraph somebody read once in 2026.

Table-driven tests are the Go idiom that fits this job precisely. Each row is a documented response body plus the struct value it should decode into, and the test loop is five lines. Ask Atlas to build the table from the samples in the fetched documentation, so the field names in the table came from the vendor rather than from the model. When go test passes, you have real evidence that the struct tags are right, which is the failure mode that would otherwise ship silently. Add the dependency, if the integration needs one, through go mod so go.sum stays consistent, then run gofmt and review the diff. Atlas reads git branches, status, and diffs, and can stage and create commits, so the client package and its tests land together.

When should Atlas search the web instead of reading the Go module?

Atlas leaves the repository only when the answer is not in the repository. An internal interface question is answered by codebase_search and grep against your Go packages. The current shape of a vendor's REST API in 2026 is not in your repository at all, and that is exactly the case websearch and webfetch exist for.

The distinction is worth being explicit about, because an agent that reaches for the network by default wastes time and leaks context, while one that never reaches for it hallucinates. Atlas's split is clean. Questions about your own module (which package owns retries, what does this interface require, is context.Context threaded through) are answered locally with codebase_search, grep, read, and the lsp tool. Questions about the outside world (what does this endpoint return, what error codes does it document, is this parameter still supported) go to websearch and webfetch, once, behind a permission prompt, and the result becomes context for the code Atlas writes. Everything after the fetch happens locally with write, edit, gofmt, and go test.

Step by step

01Start atlas in the module root, the directory that holds go.mod, so Atlas can read your packages, interfaces, and go.sum dependencies.
02Ask Atlas to call websearch for the API's current documentation page; the tool injects the current year into its description so the model biases toward fresh 2026 sources.
03Have Atlas call webfetch on that page with format markdown or text, so the Accept header steers the server toward a compact representation.
04Approve the webfetch permission prompt, which shows the URL as the pattern before any request leaves your machine.
05Grep the module for the existing error-wrapping idiom, the context.Context convention, and the interface your other packages expect an outbound client to satisfy.
06Let Atlas write the client package with write or edit against the real signatures, giving every struct field a json tag taken from the fetched payload, and approve the unified diff.
07Add any new dependency through go mod so go.sum stays consistent with the module.
08Run gofmt on the changed files and go test on the table-driven tests built from the documented response bodies.

Frequently asked questions

How do I stop an AI agent from hallucinating a REST API in my Go client?: Make it fetch the page. Atlas calls websearch to locate the current documentation and webfetch to pull it into context with format markdown or text, then writes the Go struct tags from the real payload and verifies them with table-driven go test cases.
Does Atlas upload my Go code when it fetches API documentation?: No. webfetch pulls a URL into context and nothing more. The permission prompt shows the URL as the pattern before any request goes out, and every Atlas tool call is permission-gated against allow, ask, and deny rules, so context cannot be quietly exfiltrated to arbitrary hosts.
Why do wrong JSON struct tags in Go fail silently?: Because encoding/json simply leaves the field at its zero value when the key is absent. Nothing errors. Writing the tag from the fetched documentation rather than from memory is the only reliable defense, which is why Atlas researches the API before writing the client.
Will Atlas match my module's existing error handling in a new client package?: Yes, if you let it grep first. Atlas checks the repo's own conventions with grep before committing to a pattern, so the new client wraps errors and threads context.Context the way the rest of your Go packages already do.
Does Atlas update go.mod and go.sum for a new dependency?: Atlas adds dependencies through go mod so go.sum stays consistent with your module. The command runs through a permission-gated bash call, and Atlas surfaces a unified diff for every file edit before writing.
How should I test a Go API client that Atlas generated?: With table-driven tests run by go test, one row per documented response body including the error codes the reference lists. Ask Atlas to build the table from the fetched samples so the field names come from the vendor rather than from the model.
When does Atlas use websearch instead of searching my repository?: Only when the answer is not in the repository. Questions about your own Go packages go to codebase_search, grep, and the lsp tool. Questions about a vendor's current endpoint shape go to websearch and webfetch, once, behind an explicit permission prompt.

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