with-tools

with-tools — custom tool + MCP servers + skills

What this shows

An agent composed from the three tool sources a real embedding uses:

1. a custom function tool (add, defined inline with ADK's functiontool.New),
2. MCP servers loaded from .agents/mcp.json in the working directory (if present), and
3. SKILL.md skills from .agents/skills/ (if any).

The agent is asked "What is 17 + 25?" and calls the add tool; the function-call name prints to stderr, the streamed answer to stdout.

Run it

Needs real Anthropic credentials (the example pins provider=anthropic):

ANTHROPIC_API_KEY=... go run ./examples/with-tools

MCP + skills loading is best-effort — with no .agents/ directory in your cwd it just logs and continues.

Key APIs

• functiontool.New — google.golang.org/adk/tool/functiontool
• agent.WithTools / agent.WithToolsets — github.com/go-steer/core-agent/v2/pkg/agent
• mcp.Build — github.com/go-steer/core-agent/v2/pkg/mcp
• skills.Load — github.com/go-steer/core-agent/v2/pkg/skills
• permissions.FromConfig — github.com/go-steer/core-agent/v2/pkg/permissions

What you should see

→ add
The sum of 17 and 25 is 42.

(the → add line is the model's function call, printed to stderr).

Next

• with-subagent — delegate to a second agent instead of a function tool.
• streaming — the built-in tool registry with chat rendering.
• Library guide: docs/site/src/content/docs/embed/guide.md