The quick read
- Document each tool’s allowed inputs, authentication context and possible side effects.
- Prefer small operations with clear results and limited permissions.
Separate words from effects
A prompt-only workflow produces text for a person or another system to interpret. Tool calling lets an application expose specific operations and structured arguments. A model’s request to call a tool is still a proposal that application code must validate and execute.
Compare control points
Document each tool’s allowed inputs, authentication context and possible side effects. Test malformed arguments, repeated requests and unavailable services. Free-form instructions are insufficient protection for actions such as sending messages or changing records.
Expose narrow capabilities
Prefer small operations with clear results and limited permissions. Require review for consequential actions, and make retries safe where possible. Keep a readable activity trail so a user can distinguish what the assistant suggested from what the system actually completed.
Sources & notes
An editorial decision framework, not a scored benchmark or hands-on test.
anthropic.com — official reference
genai.owasp.org — official reference
Sources reviewed for the September 2026 launch edition.