Hermes Agent + PostOnce

Connect Hermes Agent to your social accounts

Use Hermes Agent to publish updates through PostOnce, check delivery, and manage automatic crossposting between your connected accounts.

Connect Hermes Agent

Requires a PostOnce account, API access, and your own API key.

See setup steps

Set up your connection

Connect Hermes Agent to PostOnce

Use your own PostOnce API key.

1
Prepare your PostOnce account
You need API access on your plan and at least one connected social account. Create a dedicated key with accounts:read for your first check; add posts, media, or workflow scopes only for the actions you want.
Create an API key Connect social accounts Check plan access
2
Add PostOnce to your active Hermes profile
Merge this entry into the active profile’s config.yaml, preserving other servers and any existing PostOnce trust or tool filters. The default profile uses ~/.hermes/config.yaml; named profiles have their own files. This native MCP setup was checked with Hermes 0.21.0.
Active Hermes profile · config.yaml · merge into mcp_servers
```
mcp_servers:
  postonce:
    url: "https://postonce.to/mcp"
    headers:
      Authorization: "Bearer ${POSTONCE_API_KEY}"
```
Follow the client-specific instructions above. Keep your API key out of agent conversations and public files.
Set POSTONCE_API_KEY privately in the active Hermes profile’s .env file or process environment. The default profile uses ~/.hermes/.env. Keep the environment reference in config.yaml; never paste the key into chat or the skill.
Restart Hermes after saving the configuration and key. In an existing session, run /reload to refresh environment values, then /reload-mcp to reconnect MCP servers.
Preserve your existing MCP tool filters and trust settings. Installing the skill does not change them. Hermes can request tool approval when the server is configured as untrusted; some versions also prompt for read-only operations.
An untrusted server can request approval even for read tools, depending on the Hermes and MCP SDK versions. Review the request and keep your existing restrictions. A different host or profile needs its own configuration and private environment.
3
Check the connection
Ask Hermes to show your connected PostOnce accounts and their capabilities. An empty account list is a successful connection with no usable social accounts; connect the intended account in PostOnce and refresh.
Try this prompt
Show my connected social accounts.
Expect account names, platforms, and IDs from list_active_accounts. Choose actual accounts before asking the agent to publish.

Optional · after connecting

Add the PostOnce workflow skill

Give Hermes Agent reusable guidance for choosing accounts, preparing media, publishing, and checking delivery. Installing the skill adds instructions; it does not authenticate or grant access.

Read the PostOnce skill, then run the installer in your intended Hermes profile:
Terminal · install the PostOnce skill
```
hermes skills install https://postonce.to/agent-skills/postonce/SKILL.md
```
Review the installer’s scanner report and confirmation. URL skills pass through Hermes’s quarantine and installation policy. Preserve an existing PostOnce skill and its custom instructions; do not use --force to bypass a collision or scanner finding.
Start a new Hermes session and ask it to use the PostOnce skill to show your connected accounts. A different host or profile needs its own skill installation and MCP connection. Keep existing trust and tool filters, and review any approval request, including for reads.

Hermes skill documentation

Read the connection documentation

From connection to first result

Start with one useful action

Find your accounts

Try this prompt

Show my connected social accounts.

Use the returned names and IDs to choose your targets. If nothing appears, connect an account in the dashboard.

Publish an update

Try this prompt

Help me publish a product update. First show my connected accounts, then ask me to choose the destinations and confirm the exact text before publishing.

After creation, ask for the post ID and each destination’s delivery status. A queued post is still waiting to publish.

Set up crossposting

Try this prompt

Show my connected accounts and the available crossposting options. Help me choose a supported source and destinations, then confirm the workflow before creating it.

A created workflow applies to future matching source posts. Inspect the workflow in PostOnce before relying on it.

Review posts in PostOnce Review crossposting workflows

Know what your agent can access

Connected accounts and scoped actions

PostOnce uses your API key’s scopes and existing account permissions. Your available destinations come from your connected accounts; media and text requirements still vary by platform.

Media needs a supported upload path

The hosted server cannot read a file path on your computer or assume access to a chat attachment. For a first media post, use a supported publicly accessible media URL and have the agent validate the selected platform’s requirements before publishing.

Media post example

Help me publish an image from a public media URL. Ask me for the URL, text, and connected destination accounts; check the platform requirements and confirm the post before creating it.

Questions before connecting

Do I need a particular PostOnce plan?

You need a plan with Public API access. Your API keys tab checks your account’s actual entitlement and shows an upgrade option when required. Connecting a client does not change your plan.

What if my agent shows no social accounts?

Connect or reconnect a social account in PostOnce, then ask the agent to list active accounts again. The API key must belong to the same PostOnce account and include accounts:read.

How do I check a failed or queued post?

Ask the agent to get the post using its returned ID and inspect each target’s status and error. Review the post in the dashboard. Check the existing result before creating another post to avoid duplicates.

How do I disconnect or replace the key?

Revoke the dedicated API key in Preferences → API keys and remove the server from your client. To reconnect, create a new key with the scopes you need and replace the old key in the client’s private configuration.