How to integrate PromptLayer MCP with Hermes

Hermes is a 24/7 autonomous agent that lives on your computer or server — it remembers what it learns and evolves as your usage grows. This guide explains the easiest and most robust way to connect your PromptLayer account to Hermes. You can do this through either Composio Connect CLI or Composio Connect MCP. For personal use we recommend the CLI, but you won't go wrong with MCP either.

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PromptLayer is a prompt management and observability platform for LLM apps. Use it to version prompts, run evaluations, trace requests, and analyze model behavior.

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Introduction

Hermes is a 24/7 autonomous agent that lives on your computer or server — it remembers what it learns and evolves as your usage grows.

This guide explains the easiest and most robust way to connect your PromptLayer account to Hermes. You can do this through either Composio Connect CLI or Composio Connect MCP. For personal use we recommend the CLI, but you won't go wrong with MCP either.

Also integrate PromptLayer with

What is Composio Connect?

Composio Connect is a consumer offering that lets anyone plug 1,000+ applications directly into their agent harness — including Hermes. It can:

  • Search and load tools from relevant toolkits on-demand, reducing context usage.
  • Chain multiple tools to accomplish complex workflows via a remote workbench, without excessive back-and-forth with the LLM.
  • Manage app authentication end-to-end with zero manual overhead.

Integrating PromptLayer with Hermes

Using Composio Connect CLI

1. Install the Composio CLI

Run the install script directly, or paste https://composio.dev/hermes into your Hermes chat box to have it installed for you.

bash
curl -fsSL https://composio.dev/install | bash
Hermes authenticating with Composio

2. Authenticate

Once the CLI is installed, ask Hermes to authenticate with Composio.

3. Connect to PromptLayer

Ask your agent to connect to PromptLayer, or simply request any PromptLayer-related task. Hermes will prompt you to authenticate and authorize access.

4. Done. You're all set with a new PromptLayer connection.


Using Composio Connect MCP

1. Get your MCP URL and API Key

Go to dashboard.composio.dev and copy your Connect MCP URL and API key.

Copy MCP URL and API key from Composio dashboard

2. Open the Hermes config file

bash
nano ~/.hermes/config.yaml

3. Add the Composio Connect MCP server

bash
mcp_servers:
  composio:
    url: "https://connect.composio.dev/mcp"
    headers:
      x-consumer-api-key: "YOUR_COMPOSIO_API_KEY"
    connect_timeout: 60
    timeout: 180

Save with Ctrl + O, Enter, then exit with Ctrl + X.

4. Restart your Hermes agent

Once restarted, ask your agent to connect to PromptLayer or request any PromptLayer-related task. It will prompt you to authenticate and authorize access.

5. Done!

What is the PromptLayer MCP server, and what's possible with it?

The PromptLayer MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your PromptLayer account. It provides structured and secure access to your prompts, request logs, workflows, tools, skill collections, and tables, so your agent can find prompt templates, inspect LLM activity, browse workflows, review registered resources, and analyze table data on your behalf.

  • Prompt discovery and inspection: Have your agent search prompt templates and retrieve specific versions, messages, model settings, snippets, or release details for review.
  • Request monitoring and analysis: Instruct your agent to search LLM request logs and inspect recorded inputs, outputs, timing, usage, metadata, tags, and scores.
  • Workflow and tool exploration: Let the agent find workflows and registered tools, then retrieve their definitions without running them.
  • Skill and workspace browsing: Direct your agent to browse folders, registry items, and skill collections, including the files stored in a selected collection.
  • Table data review: Have your agent find tables, inspect their sheets and columns, and read rows with optional schema and execution summaries.

Way Forward

With PromptLayer connected, Hermes can now act on your behalf whenever it detects a relevant task or you ask it to.

From here, you can extend Hermes further:

  • Connect more apps: Calendar, Slack, Notion, Linear, and hundreds of others are available through the same Composio Connect setup. Each new integration compounds what Hermes can do for you.
  • Build workflows across tools: Once multiple apps are connected, Hermes can chain actions together — turn an email into a calendar invite, a Slack message into a Linear ticket, or a meeting note into a follow-up draft.
  • Let it learn your patterns: The more you use Hermes, the better it gets at anticipating how you'd handle recurring tasks. Give it feedback on drafts and decisions, and it will adapt.

If you run into trouble or want to share what you've built, join the community or check out the Docs for deeper configuration options.

TOOLS

Supported Tools

Every PromptLayer action and event your agent gets out of the box.

Get Prompt Template

Retrieve a prompt template version, release label, messages, model metadata, snippets, and optionally provider-ready kwargs without executing it.

Get Registered Tool

Retrieve a PromptLayer registered tool definition by ID or name at a selected version or release label without test execution.

Get Request Log

Retrieve one PromptLayer request log with its recorded input, output, timing, usage, metadata, tags, and scores.

Get Skill Collection

Retrieve a PromptLayer skill collection and its files as JSON at a selected version or release label.

Get Table

Retrieve one PromptLayer Table's metadata and per-sheet row counts by UUID.

Get Workflow

Retrieve a PromptLayer workflow definition by ID or name at a specific version or release label without running it.

List Folder Entities

Browse or search PromptLayer folders and registry entities in the API-key workspace, optionally recursively and with metadata.

List Prompt Templates

Search and page through PromptLayer prompt templates and snippets without executing a model.

List Registered Tools

List and filter tools defined in PromptLayer's tool registry without executing them.

List Skill Collections

List and filter PromptLayer skill collections available in the API-key workspace.

List Table Columns

List one page of user and optionally system columns for a PromptLayer Table sheet.

List Table Rows

Read one page of rows and cells from a PromptLayer Table sheet, with optional schema and execution aggregates.

List Tables

Search and page through PromptLayer Tables by folder, name, or referenced prompt.

List Table Sheets

List one page of sheets in a PromptLayer Table, optionally filtering by referenced prompt.

List Workflows

Search and page through PromptLayer workflows without running them.

Search Request Logs

Search PromptLayer request logs by text or structured filters and return one rate-limited page sorted by operational fields.

FAQ

Frequently asked questions

With a standalone PromptLayer MCP server, the agents and LLMs can only access a fixed set of PromptLayer tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from PromptLayer and many other apps based on the task at hand, all through a single MCP endpoint.

Yes, you can. Hermes fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right PromptLayer tools.

Yes, absolutely. You can configure which PromptLayer scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do.

All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your PromptLayer data and credentials are handled as safely as possible.

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