Prompts

Aether assembles system prompts from authored prompt sources and MCP server instructions into a single system prompt for each agent.

Prompt sources

The prompts field in settings.json accepts four source types:

• file-path strings such as "AGENTS.md"
• typed file sources such as { "type": "file", "path": ".aether/DEFAULT.md" }
• typed glob sources such as { "type": "glob", "pattern": "prompts/*.md" }
• inline text sources such as { "type": "text", "text": "Always answer concisely." }

Top-level prompts are defaults. An agent inherits them only when its own prompts array is empty. If an agent provides a non-empty prompts array, that array replaces the top-level prompt list for that agent.

.aether/settings.json

{
  "prompts": ["AGENTS.md"],
  "agents": [
    {
      "name": "coder",
      "description": "Coding agent",
      "model": "anthropic:claude-sonnet-4-5",
      "userInvocable": true,
      "prompts": [
        ".aether/agents/coder/CODER.md",
        { "type": "glob", "pattern": "prompts/*.md" }
      ]
    }
  ]
}

A common convention is to place an AGENTS.md at the project root with shared instructions:

AGENTS.md

# Project Agent

You are a coding assistant for this Rust project.

## Rules
- Always read files before editing them
- Write tests for new functionality
- Use `cargo clippy` to check for warnings

Note

Prompt file paths and glob patterns must match at least one file. Aether reports a validation error if a path or pattern matches nothing.

Debugging prompts

Use show-prompt to see the fully assembled system prompt for any agent:

aether show-prompt
# Inspect a specific agent
aether show-prompt -a researcher
aether show-prompt -C /path/to/project