Built-in Tools

• Key points are in the visual diagram above.

Coding agents need a small, boring tool set more than eighty vague plugins.

A kitchen: knife, board, stove. You add a thermometer. You do not add a chainsaw by default.

Scenario

A kitchen: knife, board, stove. You add a thermometer. You do not add a chainsaw by default.

Solution

In Claude Agent SDK, apply Built-in Tools to this scenario: A kitchen: knife, board, stove. Identify the inputs, run the technique, validate the output, and note one thing you would monitor in production.

Do this before moving to the next module — reading alone is not enough.

Open the Code Walkthrough below and run it locally. Change one parameter related to Built-in Tools (e.g. model, temperature, top_k, or tool name), observe the difference in output, and write 2–3 sentences explaining what changed.

Highlighted lines show where Built-in Tools happens in the code.

1options: { allowedTools: ["Read", "Grep"], disallowedTools: ["Bash"] }  # key line for Built-in Tools

• Skipping evaluation for Built-in Tools before production
• No logging or tracing around claude builtin tools steps
• Ignoring cost and latency implications

Quick recap — the most important points from this module.