feat: Phase F-3 + F-4 — exp backoff + agent tool surface (batch 1)

F-3 refinements:
- internal/inbound: replace fixed 3s reconnect wait with exponential
  backoff (1s → 60s, ×2, reset when prior session lasted >30s); proxy
  for "healthy" vs "flapping" and avoids hot reconnect loops when the
  server is sick

F-4 agent tool surface (port of openclaw plugin's tools.ts):
- internal/tools/tools.go (~370 LOC): Registry binds Deps {Client,
  Tokens, Identities} and exposes 8 agent-facing tools:
    fabric-send-message     post a normal message to any channel
    fabric-send-sys-msg     post a kind=sys message (bypasses turn engine)
    fabric-channel-list     list channels visible in a guild
    fabric-guild-list       list guilds the agent is in
    fabric-message-history  paginate channel messages by seq
    fabric-channel-set-purpose  PATCH the channel's purpose
    fabric-channel          fetch metadata + members for one channel
    fabric-canvas           get/share/update/remove channel canvas
- internal/tools/contracts.go: static ToolContract list — kept in sync
  with install.sh's manifest emitter
- Every agent-scoped tool requires agent_id in input args (Plexum SDK
  doesn't propagate calling agent id through CallTool today)
- guild_node_id defaults to agent's first guild for fabric-send-message

internal/fabric/client.go: new REST methods needed by tools —
PostSystemMessage, CreateChannel, CloseChannel, JoinChannel,
LeaveChannel, SetChannelPurpose, GetCanvas, ShareCanvas, UpdateCanvas,
RemoveCanvas, SyncCommands.

cmd/plexum-fabric-channel-plugin/main.go:
- Manifest declares the tool surface via tools.New(...).Contracts()
- CallTool dispatches "send" to handleSend (outbound for channel
  manager), everything else to tools.Registry.Handler(name)

scripts/install.sh:
- Manifest tools[] now lists all 9 tools with schemas — matches what
  internal/tools/contracts.go advertises

Live verified against running Fabric stack:
  $ plexum plugin-call fabric-guild-list '{"agent_id":"fabrictester"}'
    → "guilds for agent fabrictester (1): test-guild2 @ http://localhost:7003"
  $ plexum plugin-call fabric-channel-list '{...,"guild_node_id":"test-guild2"}'
    → 2 channels listed
  $ plexum plugin-call fabric-message-history '{...,"limit":5}'
    → 5 messages with timestamps + authors

F-5+ deferred:
- create-{chat,work,report,discussion}-channel (batch 2)
- sub-discussion family (state store + 3 tools)
- presence-sync + command-sync
- attachments

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
This commit is contained in:
h z
2026-05-31 15:35:39 +01:00
parent 0efcdfd342
commit d6bea46d00
6 changed files with 825 additions and 54 deletions

442
internal/tools/tools.go Normal file
View File

@@ -0,0 +1,442 @@
// Package tools implements the Fabric-specific MCP tools the plugin
// exposes to Plexum agents (port of openclaw plugin's tools.ts, F-4 +
// F-5 + F-7 split). Each tool here is bound to a Plexum context that
// gives it access to:
//
// - fabric.Client for REST calls
// - tokens.Cache for per-agent session reuse + auto-refresh
// - identity.Registry to look up agent → fabric user_id
// - the plugin's logger
//
// Per-tool agent identity: Plexum SDK doesn't propagate the calling
// agent id through CallTool today, so every agent-scoped tool here
// requires `agent_id` in input args. The agent learns its own id from
// the host (env var or system prompt — operator concern).
package tools
import (
"context"
"encoding/json"
"fmt"
"strings"
plugin "git.hangman-lab.top/hzhang/Plexum-sdk-go/plugin"
"git.hangman-lab.top/hzhang/Plexum-fabric-channel-plugin/internal/fabric"
"git.hangman-lab.top/hzhang/Plexum-fabric-channel-plugin/internal/identity"
"git.hangman-lab.top/hzhang/Plexum-fabric-channel-plugin/internal/tokens"
)
// Deps bundles what every tool needs.
type Deps struct {
Client *fabric.Client
Tokens *tokens.Cache
Identities *identity.Registry
}
// HandlerFunc is the tool's call-time function. Returns a ToolResult
// (text content) or an in-band error result (IsError=true).
type HandlerFunc func(ctx context.Context, input json.RawMessage) (plugin.ToolResult, error)
// Registry maps tool name → HandlerFunc. Build once at plugin init.
type Registry struct {
deps Deps
handlers map[string]HandlerFunc
}
// New constructs a Registry with the agent-facing tools wired.
func New(deps Deps) *Registry {
r := &Registry{deps: deps, handlers: map[string]HandlerFunc{}}
r.registerSendMessage()
r.registerSendSysMsg()
r.registerChannelList()
r.registerGuildList()
r.registerMessageHistory()
r.registerChannelSetPurpose()
r.registerChannel()
r.registerCanvas()
return r
}
// Names returns the registered tool names (for manifest generation).
func (r *Registry) Names() []string {
out := make([]string, 0, len(r.handlers))
for k := range r.handlers {
out = append(out, k)
}
return out
}
// Handler returns the function for `name`, or nil if not registered.
func (r *Registry) Handler(name string) HandlerFunc {
return r.handlers[name]
}
// Contracts returns the MCP ToolContracts for all registered tools.
// Used by install.sh / manifest generation; also useful for runtime
// introspection.
func (r *Registry) Contracts() []plugin.ToolContract {
return allContracts
}
// ---- helpers ----
func textResult(text string) plugin.ToolResult {
return plugin.NewTextResult(text)
}
func errResult(msg string) plugin.ToolResult {
return plugin.ToolResult{
Content: []plugin.ContentBlock{{Type: "text", Text: msg}},
IsError: true,
}
}
func jsonResult(label string, body any) plugin.ToolResult {
raw, err := json.MarshalIndent(body, "", " ")
if err != nil {
return errResult(label + ": marshal: " + err.Error())
}
return textResult(label + ":\n" + string(raw))
}
// agentGuild resolves the agent's session + the specified guild's
// endpoint + token. Common preamble for every tool that hits a guild.
func (r *Registry) agentGuild(ctx context.Context, agentID, guildNodeID string) (sess *fabric.Session, endpoint, token string, err error) {
if agentID == "" {
err = fmt.Errorf("agent_id is required")
return
}
sess, err = r.deps.Tokens.Get(ctx, agentID)
if err != nil {
return
}
for _, g := range sess.Guilds {
if g.NodeID == guildNodeID {
endpoint = g.Endpoint
break
}
}
for _, t := range sess.GuildAccessTokens {
if t.GuildNodeID == guildNodeID {
token = t.Token
break
}
}
if endpoint == "" || token == "" {
err = fmt.Errorf("agent %s has no access to guild %s", agentID, guildNodeID)
}
return
}
// pickFirstGuild returns the first guild from the session when caller
// omits guild_node_id. Most agents are in exactly one guild, so this is
// a no-arg sane default.
func pickFirstGuild(sess *fabric.Session) (string, error) {
for _, g := range sess.Guilds {
if g.NodeID != "" {
return g.NodeID, nil
}
}
return "", fmt.Errorf("agent has no guilds")
}
// ---- tool: fabric-send-message ----
func (r *Registry) registerSendMessage() {
r.handlers["fabric-send-message"] = func(ctx context.Context, raw json.RawMessage) (plugin.ToolResult, error) {
var in struct {
AgentID string `json:"agent_id"`
GuildNodeID string `json:"guild_node_id"`
ChannelID string `json:"channel_id"`
Content string `json:"content"`
}
if err := json.Unmarshal(raw, &in); err != nil {
return errResult("fabric-send-message: parse: " + err.Error()), nil
}
if in.ChannelID == "" || in.Content == "" {
return errResult("fabric-send-message: channel_id and content required"), nil
}
sess, endpoint, token, err := r.agentGuild(ctx, in.AgentID, in.GuildNodeID)
if err != nil {
if in.GuildNodeID == "" && in.AgentID != "" {
// Try first-guild fallback.
if s2, err2 := r.deps.Tokens.Get(ctx, in.AgentID); err2 == nil {
if gn, err3 := pickFirstGuild(s2); err3 == nil {
in.GuildNodeID = gn
sess, endpoint, token, err = r.agentGuild(ctx, in.AgentID, in.GuildNodeID)
}
}
}
if err != nil {
return errResult("fabric-send-message: " + err.Error()), nil
}
}
if err := r.deps.Client.PostMessage(ctx, endpoint, token, in.ChannelID, in.Content, sess.User.ID); err != nil {
return errResult("fabric-send-message: post: " + err.Error()), nil
}
return textResult(fmt.Sprintf("sent: guild=%s channel=%s len=%d",
in.GuildNodeID, in.ChannelID, len(in.Content))), nil
}
}
// ---- tool: fabric-send-sys-msg ----
func (r *Registry) registerSendSysMsg() {
r.handlers["fabric-send-sys-msg"] = func(ctx context.Context, raw json.RawMessage) (plugin.ToolResult, error) {
var in struct {
AgentID string `json:"agent_id"`
GuildNodeID string `json:"guild_node_id"`
ChannelID string `json:"channel_id"`
Content string `json:"content"`
}
if err := json.Unmarshal(raw, &in); err != nil {
return errResult("fabric-send-sys-msg: parse: " + err.Error()), nil
}
if in.ChannelID == "" || in.Content == "" {
return errResult("fabric-send-sys-msg: channel_id and content required"), nil
}
sess, endpoint, token, err := r.agentGuild(ctx, in.AgentID, in.GuildNodeID)
if err != nil {
return errResult("fabric-send-sys-msg: " + err.Error()), nil
}
if err := r.deps.Client.PostSystemMessage(ctx, endpoint, token, in.ChannelID, in.Content, sess.User.ID); err != nil {
return errResult("fabric-send-sys-msg: post: " + err.Error()), nil
}
return textResult("system message sent"), nil
}
}
// ---- tool: fabric-channel-list ----
func (r *Registry) registerChannelList() {
r.handlers["fabric-channel-list"] = func(ctx context.Context, raw json.RawMessage) (plugin.ToolResult, error) {
var in struct {
AgentID string `json:"agent_id"`
GuildNodeID string `json:"guild_node_id"`
}
if err := json.Unmarshal(raw, &in); err != nil {
return errResult("fabric-channel-list: parse: " + err.Error()), nil
}
_, endpoint, token, err := r.agentGuild(ctx, in.AgentID, in.GuildNodeID)
if err != nil {
return errResult("fabric-channel-list: " + err.Error()), nil
}
channels, err := r.deps.Client.ListChannels(ctx, endpoint, token, in.GuildNodeID)
if err != nil {
return errResult("fabric-channel-list: " + err.Error()), nil
}
// Compact rendering — table-ish.
var b strings.Builder
fmt.Fprintf(&b, "channels in guild %s (%d):\n", in.GuildNodeID, len(channels))
for _, c := range channels {
purpose := ""
if c.Purpose != nil {
purpose = " — " + *c.Purpose
}
fmt.Fprintf(&b, " %s [%s] %s%s\n", c.ID, c.XType, c.Name, purpose)
}
return textResult(b.String()), nil
}
}
// ---- tool: fabric-guild-list ----
func (r *Registry) registerGuildList() {
r.handlers["fabric-guild-list"] = func(ctx context.Context, raw json.RawMessage) (plugin.ToolResult, error) {
var in struct {
AgentID string `json:"agent_id"`
}
if err := json.Unmarshal(raw, &in); err != nil {
return errResult("fabric-guild-list: parse: " + err.Error()), nil
}
if in.AgentID == "" {
return errResult("fabric-guild-list: agent_id required"), nil
}
sess, err := r.deps.Tokens.Get(ctx, in.AgentID)
if err != nil {
return errResult("fabric-guild-list: " + err.Error()), nil
}
var b strings.Builder
fmt.Fprintf(&b, "guilds for agent %s (%d):\n", in.AgentID, len(sess.Guilds))
for _, g := range sess.Guilds {
purpose := ""
if g.Purpose != nil {
purpose = " — " + *g.Purpose
}
fmt.Fprintf(&b, " %s @ %s (%s)%s\n", g.NodeID, g.Endpoint, g.Name, purpose)
}
return textResult(b.String()), nil
}
}
// ---- tool: fabric-message-history ----
func (r *Registry) registerMessageHistory() {
r.handlers["fabric-message-history"] = func(ctx context.Context, raw json.RawMessage) (plugin.ToolResult, error) {
var in struct {
AgentID string `json:"agent_id"`
GuildNodeID string `json:"guild_node_id"`
ChannelID string `json:"channel_id"`
SeqFrom int `json:"seq_from"`
SeqTo int `json:"seq_to"`
Limit int `json:"limit"`
}
if err := json.Unmarshal(raw, &in); err != nil {
return errResult("fabric-message-history: parse: " + err.Error()), nil
}
if in.ChannelID == "" {
return errResult("fabric-message-history: channel_id required"), nil
}
_, endpoint, token, err := r.agentGuild(ctx, in.AgentID, in.GuildNodeID)
if err != nil {
return errResult("fabric-message-history: " + err.Error()), nil
}
page, err := r.deps.Client.ListMessages(ctx, endpoint, token, in.ChannelID,
fabric.ListMessagesOpts{SeqFrom: in.SeqFrom, SeqTo: in.SeqTo, Limit: in.Limit})
if err != nil {
return errResult("fabric-message-history: " + err.Error()), nil
}
var b strings.Builder
fmt.Fprintf(&b, "history channel=%s seq=%d-%d returned=%d hasMore=%v\n",
in.ChannelID, page.Page.SeqFrom, page.Page.SeqTo, page.Page.Returned, page.Page.HasMore)
for _, m := range page.Items {
marker := ""
if m.IsDeleted {
marker = " (deleted)"
} else if m.EditedAt != nil {
marker = " (edited)"
}
fmt.Fprintf(&b, " seq=%d %s by %s%s: %s\n",
m.Seq, m.CreatedAt, m.AuthorUserID, marker, m.Content)
}
return textResult(b.String()), nil
}
}
// ---- tool: fabric-channel-set-purpose ----
func (r *Registry) registerChannelSetPurpose() {
r.handlers["fabric-channel-set-purpose"] = func(ctx context.Context, raw json.RawMessage) (plugin.ToolResult, error) {
var in struct {
AgentID string `json:"agent_id"`
GuildNodeID string `json:"guild_node_id"`
ChannelID string `json:"channel_id"`
Purpose string `json:"purpose"`
}
if err := json.Unmarshal(raw, &in); err != nil {
return errResult("fabric-channel-set-purpose: parse: " + err.Error()), nil
}
if in.ChannelID == "" {
return errResult("fabric-channel-set-purpose: channel_id required"), nil
}
_, endpoint, token, err := r.agentGuild(ctx, in.AgentID, in.GuildNodeID)
if err != nil {
return errResult("fabric-channel-set-purpose: " + err.Error()), nil
}
if err := r.deps.Client.SetChannelPurpose(ctx, endpoint, token, in.ChannelID, in.Purpose); err != nil {
return errResult("fabric-channel-set-purpose: " + err.Error()), nil
}
return textResult(fmt.Sprintf("purpose updated for %s", in.ChannelID)), nil
}
}
// ---- tool: fabric-channel (meta about one channel) ----
func (r *Registry) registerChannel() {
r.handlers["fabric-channel"] = func(ctx context.Context, raw json.RawMessage) (plugin.ToolResult, error) {
var in struct {
AgentID string `json:"agent_id"`
GuildNodeID string `json:"guild_node_id"`
ChannelID string `json:"channel_id"`
}
if err := json.Unmarshal(raw, &in); err != nil {
return errResult("fabric-channel: parse: " + err.Error()), nil
}
if in.ChannelID == "" {
return errResult("fabric-channel: channel_id required"), nil
}
_, endpoint, token, err := r.agentGuild(ctx, in.AgentID, in.GuildNodeID)
if err != nil {
return errResult("fabric-channel: " + err.Error()), nil
}
// Find by scanning channel list — guild has no GET-one endpoint.
channels, err := r.deps.Client.ListChannels(ctx, endpoint, token, in.GuildNodeID)
if err != nil {
return errResult("fabric-channel: " + err.Error()), nil
}
for _, c := range channels {
if c.ID == in.ChannelID {
members, _ := r.deps.Client.ChannelMembers(ctx, endpoint, token, in.ChannelID)
return jsonResult("channel", map[string]any{
"channel": c, "members": members,
}), nil
}
}
return errResult("fabric-channel: channel " + in.ChannelID + " not found in guild"), nil
}
}
// ---- tool: fabric-canvas (get / share / update / remove) ----
func (r *Registry) registerCanvas() {
r.handlers["fabric-canvas"] = func(ctx context.Context, raw json.RawMessage) (plugin.ToolResult, error) {
var in struct {
AgentID string `json:"agent_id"`
GuildNodeID string `json:"guild_node_id"`
ChannelID string `json:"channel_id"`
Op string `json:"op"` // "get" | "share" | "update" | "remove"
Title string `json:"title"`
Format string `json:"format"` // "md" | "html" | "text"
Source string `json:"source"`
}
if err := json.Unmarshal(raw, &in); err != nil {
return errResult("fabric-canvas: parse: " + err.Error()), nil
}
if in.ChannelID == "" {
return errResult("fabric-canvas: channel_id required"), nil
}
if in.Op == "" {
in.Op = "get"
}
_, endpoint, token, err := r.agentGuild(ctx, in.AgentID, in.GuildNodeID)
if err != nil {
return errResult("fabric-canvas: " + err.Error()), nil
}
switch in.Op {
case "get":
canvas, err := r.deps.Client.GetCanvas(ctx, endpoint, token, in.ChannelID)
if err != nil {
return errResult("fabric-canvas: " + err.Error()), nil
}
if canvas == nil {
return textResult("(no canvas set on this channel)"), nil
}
return jsonResult("canvas", canvas), nil
case "share":
if in.Title == "" || in.Source == "" || in.Format == "" {
return errResult("fabric-canvas share: title + format + source required"), nil
}
canvas, err := r.deps.Client.ShareCanvas(ctx, endpoint, token, in.ChannelID,
in.Title, fabric.CanvasFormat(in.Format), in.Source)
if err != nil {
return errResult("fabric-canvas share: " + err.Error()), nil
}
return jsonResult("canvas shared", canvas), nil
case "update":
canvas, err := r.deps.Client.UpdateCanvas(ctx, endpoint, token, in.ChannelID,
in.Title, in.Source, fabric.CanvasFormat(in.Format))
if err != nil {
return errResult("fabric-canvas update: " + err.Error()), nil
}
return jsonResult("canvas updated", canvas), nil
case "remove":
if err := r.deps.Client.RemoveCanvas(ctx, endpoint, token, in.ChannelID); err != nil {
return errResult("fabric-canvas remove: " + err.Error()), nil
}
return textResult("canvas removed"), nil
default:
return errResult("fabric-canvas: unknown op " + in.Op + " (want get|share|update|remove)"), nil
}
}
}