Method fetchSpec

pkg/tools/builtin/openapi/openapi.go:117–164

fetchSpec retrieves and parses the OpenAPI specification from the configured URL.

(ctx context.Context)

// fetchSpec retrieves and parses the OpenAPI specification from the configured URL.
func (t *ToolSet) fetchSpec(ctx context.Context) (*v3.Document, error) {
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, t.specURL, http.NoBody)
	if err != nil {
		return nil, fmt.Errorf("failed to create request: %w", err)
	}

	req.Header.Set("Accept", "application/json")
	setHeaders(req, t.headers)

	resp, err := httpclient.NewSafeClient(t.timeout, t.allowPrivateIPs).Do(req)
	if err != nil {
		return nil, fmt.Errorf("request failed: %w", err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("unexpected status code %d", resp.StatusCode)
	}

	limitedReader := io.LimitReader(resp.Body, 10<<20) // 10MB limit
	body, err := io.ReadAll(limitedReader)
	if err != nil {
		return nil, fmt.Errorf("failed to read response: %w", err)
	}

	// Check if the spec was truncated.
	if len(body) >= 10<<20 {
		return nil, errors.New("OpenAPI spec exceeds 10MB size limit")
	}

	doc, err := libopenapi.NewDocument(body)
	if err != nil {
		return nil, fmt.Errorf("failed to parse OpenAPI spec: %w", err)
	}

	model, buildErr := doc.BuildV3Model()
	if buildErr != nil {
		// Log validation issues but don't fail — some valid OpenAPI 3.1
		// features may not be fully supported by the validator.
		slog.WarnContext(ctx, "OpenAPI spec validation reported issues; proceeding anyway", "url", t.specURL, "error", buildErr)
	}

	if model == nil {
		return nil, errors.New("failed to build OpenAPI V3 model from spec")
	}

	return &model.Model, nil
}

// buildTools converts an OpenAPI spec into a list of tools.
func (t *ToolSet) buildTools(spec *v3.Document) ([]tools.Tool, error) {