Update Contact

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Discloses dry-run behavior and confirmation requirement, but no mention of side effects, error handling, or permissions. With no annotations, more detail expected.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two concise sentences, front-loaded with purpose. No redundant words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Missing details on 'changes' object structure, return value, error states. For a mutation tool with nested parameter, this is insufficient.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Only adds meaning to dryRun and confirm parameters. The 'changes' object parameter lacks any structural description. Schema coverage is 0%, so description should compensate more.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Clearly states verb 'Update' and resource 'Apple Contact by contactId'. Distinguishes from siblings like create_contact and delete_contact.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly notes dry-run default and requirement of dryRun=false and confirm=true for actual writes. Provides clear context for safe usage.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.