feat(web-search): add AI/ML API Toolbox as an opt-in backend

README.md

@@ -397,6 +397,31 @@ and can rewrite every request through it, so this is the trust you accept by
 configuring one. Leave the variables unset for the checks to be enforced end to
 end.
 
+The built-in `web_search` tool is registered only when a search backend is
+configured: `ZERO_WEBSEARCH_BASE_URL` (with an optional `ZERO_WEBSEARCH_API_KEY`)
+for a generic JSON endpoint, `ZERO_WEBSEARCH_PROVIDER=searxng` with a SearXNG
+base URL, or the AI/ML API Toolbox:
+
+```bash
+export ZERO_WEBSEARCH_PROVIDER=aimlapi
+```
+
+The AI/ML API backend runs the Toolbox tool `web/search`, and every search is
+billed to your AI/ML API balance: about $0.0013 per result, with a documented
+minimum of $0.0091 per search. Each search is sent with a $0.025 spending cap,
+which the Toolbox enforces. It is used only when
+`ZERO_WEBSEARCH_PROVIDER` is set to `aimlapi`; an AI/ML API key alone never
+enables it. The key is the one the aimlapi provider uses (its profile, including
+a key in the credential store, or `AIMLAPI_API_KEY` without a profile), resolved
+again on every search; `ZERO_WEBSEARCH_API_KEY` is not used. When an aimlapi
+profile points at a base URL other than `https://api.aimlapi.com/v1`, or
+`AIMLAPI_INFERENCE_URL` is overridden, the key may belong to a proxy, so it is
+not sent and the search fails without a request. Requests go only to
+`https://tools.aimlapi.com` (`ZERO_WEBSEARCH_BASE_URL` is ignored and redirects
+are refused) and carry `X-AIMLAPI-Source: agent/zero` and an
+`X-AIMLAPI-Partner-ID` header. The `domains` argument is sent to the Toolbox as
+`include_domains`, and results are still filtered locally.
+
 For local dev servers, use shell commands such as `curl` through `exec_command`
 so the normal sandbox and permission policy applies. Long-running commands stay
 attached to a background terminal session and can be listed or stopped from the

internal/aimlapi/attribution.go

@@ -0,0 +1,57 @@
+package aimlapi
+
+import (
+	"net/http"
+	"net/url"
+	"strings"
+)
+
+const (
+	// SourceHeaderName and SourceValue identify Zero as the calling agent on
+	// requests to aimlapi.com services (the Toolbox and the MCP server).
+	SourceHeaderName = "X-AIMLAPI-Source"
+	SourceValue      = "agent/zero"
+
+	// CanonicalInferenceBaseURL is the catalog inference endpoint. A provider
+	// profile whose base URL differs is treated as a proxy: its key is never sent
+	// to other aimlapi.com services.
+	CanonicalInferenceBaseURL = "https://api.aimlapi.com/v1"
+	// ToolboxBaseURL is the fixed AI/ML API Toolbox REST base. It is not
+	// configurable, so the key and attribution can only reach tools.aimlapi.com.
+	ToolboxBaseURL = "https://tools.aimlapi.com/v1/tools"
+	// MCPServerURL is the AI/ML API MCP server (streamable HTTP).
+	MCPServerURL = "https://mcp.aimlapi.com/mcp"
+)
+
+// attributedHosts are the only hostnames that receive the AI/ML API key or the
+// attribution headers. Matching is exact; a suffix or substring match would
+// also accept hosts such as tools.aimlapi.com.example.net.
+var attributedHosts = [...]string{"api.aimlapi.com", "tools.aimlapi.com", "mcp.aimlapi.com"}
+
+// IsAttributedURL reports whether target is an https URL on one of the
+// aimlapi.com service hosts, on the default port and without userinfo.
+func IsAttributedURL(target *url.URL) bool {
+	if target == nil || !strings.EqualFold(target.Scheme, "https") || target.User != nil {
+		return false
+	}
+	if port := target.Port(); port != "" && port != "443" {
+		return false
+	}
+	host := strings.ToLower(target.Hostname())
+	for _, candidate := range attributedHosts {
+		if host == candidate {
+			return true
+		}
+	}
+	return false
+}
+
+// ApplyAttributionHeaders sets the source and partner headers on header only
+// when target is an aimlapi.com service URL; any other target is left as is.
+func ApplyAttributionHeaders(header http.Header, target *url.URL) {
+	if header == nil || !IsAttributedURL(target) {
+		return
+	}
+	header.Set(SourceHeaderName, SourceValue)
+	header.Set(PartnerHeaderName, ResolvePartnerID(""))
+}

internal/aimlapi/attribution_test.go

@@ -0,0 +1,54 @@
+package aimlapi
+
+import (
+	"net/http"
+	"net/url"
+	"testing"
+)
+
+func TestIsAttributedURLMatchesExactServiceHostsOnly(t *testing.T) {
+	cases := map[string]bool{
+		"https://tools.aimlapi.com/v1/tools/run":    true,
+		"https://mcp.aimlapi.com/mcp":               true,
+		"https://api.aimlapi.com/v1":                true,
+		"https://TOOLS.aimlapi.com:443/v1/tools":    true,
+		"http://tools.aimlapi.com/v1/tools/run":     false,
+		"https://tools.aimlapi.com:8443/v1/tools":   false,
+		"https://user@tools.aimlapi.com/v1/tools":   false,
+		"https://tools.aimlapi.com.example.net/run": false,
+		"https://eviltools.aimlapi.com/run":         false,
+		"https://aimlapi.com/app":                   false,
+		"https://auth.aimlapi.com/":                 false,
+		"https://example.com/?h=tools.aimlapi.com":  false,
+	}
+	for raw, want := range cases {
+		target, err := url.Parse(raw)
+		if err != nil {
+			t.Fatalf("parse %q: %v", raw, err)
+		}
+		if got := IsAttributedURL(target); got != want {
+			t.Errorf("IsAttributedURL(%q) = %v, want %v", raw, got, want)
+		}
+	}
+	if IsAttributedURL(nil) {
+		t.Fatal("IsAttributedURL(nil) = true")
+	}
+}
+
+func TestApplyAttributionHeadersSetsSourceAndPartnerOnServiceHosts(t *testing.T) {
+	t.Setenv("AIMLAPI_PARTNER_ID", "")
+	header := http.Header{}
+	ApplyAttributionHeaders(header, &url.URL{Scheme: "https", Host: "tools.aimlapi.com", Path: "/v1/tools/run"})
+	if got := header.Get(SourceHeaderName); got != "agent/zero" {
+		t.Fatalf("%s = %q, want agent/zero", SourceHeaderName, got)
+	}
+	if got := header.Get(PartnerHeaderName); got != DefaultPartnerID {
+		t.Fatalf("%s = %q, want %q", PartnerHeaderName, got, DefaultPartnerID)
+	}
+
+	other := http.Header{}
+	ApplyAttributionHeaders(other, &url.URL{Scheme: "https", Host: "tools.aimlapi.com.example.net"})
+	if len(other) != 0 {
+		t.Fatalf("attribution reached a non-aimlapi host: %#v", other)
+	}
+}

internal/config/aimlapi_service_key.go

@@ -0,0 +1,133 @@
+package config
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+	"unicode"
+
+	"github.com/Twigpine/zero/internal/aimlapi"
+	"github.com/Twigpine/zero/internal/providercatalog"
+)
+
+const aimlapiKeyEnv = "AIMLAPI_API_KEY"
+
+var (
+	// ErrAIMLAPIKeyMissing means no AI/ML API key is configured.
+	ErrAIMLAPIKeyMissing = errors.New("no AI/ML API key is configured; set up aimlapi.com with /provider or set AIMLAPI_API_KEY")
+	// ErrAIMLAPIProxyProfile means the aimlapi profile points at a proxy, so its
+	// key belongs to that proxy and is withheld from aimlapi.com services.
+	ErrAIMLAPIProxyProfile = errors.New("the aimlapi provider points at a proxy base URL; its key is not sent to aimlapi.com services")
+	// ErrAIMLAPIKeyInvalid means the key cannot be sent as a single Bearer token.
+	ErrAIMLAPIKeyInvalid = errors.New("the AI/ML API key contains whitespace, a comma or a control character")
+)
+
+// AIMLAPIServiceKey returns the AI/ML API key that may be sent to the
+// aimlapi.com Toolbox and MCP server. It is resolved again on every call, so a
+// provider change is seen by the next request.
+//
+// The key comes from the aimlapi provider profile (the active one when it is
+// aimlapi, otherwise the first), including a key held in the credential store,
+// or from AIMLAPI_API_KEY when no aimlapi profile exists. The key is withheld
+// when that profile, any aimlapi profile, or any profile reading
+// AIMLAPI_API_KEY points at a base URL other than the canonical
+// https://api.aimlapi.com/v1, and when AIMLAPI_INFERENCE_URL is overridden:
+// in those cases the credential may belong to a proxy.
+func AIMLAPIServiceKey(resolved ResolvedConfig, store APIKeyGetter, getenv func(string) string) (string, error) {
+	if getenv == nil {
+		getenv = os.Getenv
+	}
+	if override := strings.TrimSpace(getenv("AIMLAPI_INFERENCE_URL")); override != "" && !sameBaseURL(override, aimlapi.CanonicalInferenceBaseURL) {
+		return "", ErrAIMLAPIProxyProfile
+	}
+	for _, profile := range resolved.Providers {
+		if aimlapiKeyedProfile(profile) && !sameBaseURL(profile.BaseURL, aimlapi.CanonicalInferenceBaseURL) {
+			return "", ErrAIMLAPIProxyProfile
+		}
+	}
+	if profile, ok := aimlapiServiceProfile(resolved); ok {
+		if !sameBaseURL(profile.BaseURL, aimlapi.CanonicalInferenceBaseURL) {
+			return "", ErrAIMLAPIProxyProfile
+		}
+		if store != nil && profile.APIKeyStored && strings.TrimSpace(profile.APIKey) == "" && strings.TrimSpace(profile.Name) != "" {
+			key, found, err := store.Get(strings.TrimSpace(profile.Name))
+			if err != nil {
+				return "", fmt.Errorf("read AI/ML API credential store: %w", err)
+			}
+			if found {
+				profile.APIKey = key
+			}
+		}
+		return validAIMLAPIServiceKey(profile.APIKey)
+	}
+	return validAIMLAPIServiceKey(getenv(aimlapiKeyEnv))
+}
+
+// LoadAIMLAPIServiceKey resolves the user configuration, the environment and
+// the user credential store, then applies AIMLAPIServiceKey. Project config is
+// not read: provider keys are user-scoped.
+func LoadAIMLAPIServiceKey() (string, error) {
+	userConfigPath, err := DefaultUserConfigPath()
+	if err != nil {
+		return "", err
+	}
+	existing, err := existingConfigFile(userConfigPath)
+	if err != nil {
+		return "", err
+	}
+	resolved, err := Resolve(ResolveOptions{UserConfigPath: existing, ExcludeProject: true})
+	if err != nil {
+		return "", err
+	}
+	// Check proxy eligibility and already-resolved keys before opening a store.
+	key, keyErr := AIMLAPIServiceKey(resolved, nil, os.Getenv)
+	if !errors.Is(keyErr, ErrAIMLAPIKeyMissing) {
+		return key, keyErr
+	}
+	profile, ok := aimlapiServiceProfile(resolved)
+	if !ok || !profile.APIKeyStored {
+		return key, keyErr
+	}
+	store, err := ProviderKeyStoreAt(filepath.Dir(userConfigPath))
+	if err != nil {
+		return "", fmt.Errorf("open AI/ML API credential store: %w", err)
+	}
+	return AIMLAPIServiceKey(resolved, store, os.Getenv)
+}
+
+func isAIMLAPIProfile(profile ProviderProfile) bool {
+	return strings.EqualFold(providercatalog.NormalizeID(profile.CatalogID), providercatalog.AIMLAPIID)
+}
+
+// aimlapiKeyedProfile reports whether profile carries an AI/ML API credential:
+// an aimlapi catalog profile, or any profile that reads AIMLAPI_API_KEY.
+func aimlapiKeyedProfile(profile ProviderProfile) bool {
+	return isAIMLAPIProfile(profile) || strings.EqualFold(strings.TrimSpace(profile.APIKeyEnv), aimlapiKeyEnv)
+}
+
+func aimlapiServiceProfile(resolved ResolvedConfig) (ProviderProfile, bool) {
+	if isAIMLAPIProfile(resolved.Provider) {
+		return resolved.Provider, true
+	}
+	for _, profile := range resolved.Providers {
+		if isAIMLAPIProfile(profile) {
+			return profile, true
+		}
+	}
+	return ProviderProfile{}, false
+}
+
+func validAIMLAPIServiceKey(raw string) (string, error) {
+	key := strings.TrimSpace(raw)
+	if key == "" {
+		return "", ErrAIMLAPIKeyMissing
+	}
+	for _, r := range key {
+		if unicode.IsSpace(r) || r <= ' ' || r == 0x7f || r == ',' || (r >= 0x80 && r <= 0x9f) {
+			return "", ErrAIMLAPIKeyInvalid
+		}
+	}
+	return key, nil
+}