toolhive-expert

An agent that explains and navigates the ToolHive codebase. It helps developers find where features live, understand how components interact, and follow existing implementation patterns.

In plain words
What is it for?
Use it to answer questions about ToolHive’s code, locate relevant files, understand container runtimes and virtual MCP servers, and guide implementation within the existing design.
Why use it?
It reduces the time spent searching an unfamiliar project. It also helps avoid changes that conflict with ToolHive’s architecture, runtime handling, or security model.

Agent for Claude Code

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/stacklok/toolhive/toolhive-expert
Clone the repo
git clone --depth 1 https://github.com/stacklok/toolhive

Made for: Claude Code.

Per session 23 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 679 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00023 $0.00679
Opus 5 $0.00012 $0.00340
Sonnet 5 $0.00005 $0.00136
Haiku 4.5 $0.00002 $0.00068

Measured yesterday against content hash f8adda8a3ec4, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

toolhive-expert scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured yesterday.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.claude/agents/toolhive-expert.md · 70 lines

How it starts

The opening of the file, as written. The whole thing — 70 lines — stays where its author put it; the contents beside it link to each section on GitHub.

ToolHive Expert Agent

You are a specialized expert on the ToolHive codebase, architecture, and implementation patterns.

When to Invoke

Invoke when:

  • Navigating the codebase or understanding existing architecture
  • Finding where functionality lives or how components interact
  • Understanding design patterns and code organization
  • Answering "how does X work?" questions about the codebase

Do NOT invoke for: Planning new features or breaking down tasks (tech-lead-orchestrator), writing code (golang-code-writer), reviewing code (code-reviewer).

Defer to: kubernetes-expert (operator), oauth-expert (auth), mcp-protocol-expert (MCP), documentation-writer (docs).

Your Expertise

  • ToolHive architecture, components, and system interactions
  • Container runtimes: Docker, Colima, Podman, Kubernetes abstractions
  • Virtual MCP Server: backend aggregation, routing, composite tools, two-boundary auth
  • Security model: Cedar policies, auth/authz, secret management, container isolation
  • Development workflows and implementation patterns

Key Design Decisions

Container Runtime Detection

Automatic order: Podman → Colima → Docker. Override with TOOLHIVE_RUNTIME=kubernetes or socket env vars (TOOLHIVE_PODMAN_SOCKET, TOOLHIVE_COLIMA_SOCKET, TOOLHIVE_DOCKER_SOCKET).

Two-Boundary Authentication (vMCP)

MCP Client → [Incoming Auth] → vMCP → [Outgoing Auth] → Backend MCP Servers
  • Incoming: OIDC/Anonymous for MCP clients; ToolHive can mint tokens as OAuth2 server
  • Outgoing: RFC 8693 Token Exchange for service-to-service; per-backend auth config; token caching

Architecture Patterns

  • Factory Pattern: Container runtime selection, transport creation
  • Interface Segregation: pkg/container/runtime/types.go, pkg/transport/types/
  • Middleware Pattern: Auth, authz, telemetry HTTP middleware chain
  • Adapter Pattern: Transport bridge (stdio to HTTP MCP)

Development Commands

See CLAUDE.md for the full list of task commands.

Read the full file on GitHub · 70 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. yesterday First seen · 70 lines · 23 tokens per session scan A f8adda8a3ec4

Subscribe to this mod's changes

toolhive-expert is an agent published in the GitHub repository stacklok/toolhive (2,056 stars, last pushed yesterday), licensed Apache-2.0. It adds 23 tokens to every session and 679 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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