messages_with

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

Beyond the readOnlyHint/destructiveHint annotations, the description discloses the data source (chat.db), ordering (newest-first), the Full Disk Access requirement, and the typed error raised when access is missing. It does not cover pagination or rate-limit behavior, but adds meaningful operational context.

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?

The description is compact and front-loaded: the resource, source, ordering, contact/country semantics, and access requirement are all presented without filler. Every sentence adds useful information.

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?

Given an output schema exists, return formatting is not needed. The description covers the key behavioral constraint (Full Disk Access), source and ordering, and two of three parameters. The missing limit semantics and lack of sibling routing guidance are the only notable gaps.

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?

Schema description coverage is 0%, so the description must carry parameter meaning. It explains contact as a phone number or email and country as an optional calling code or 2-letter region with a locale-derived default, but it omits the limit parameter entirely, leaving one of three parameters undocumented.

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?

The description states a specific verb/resource: recent messages by phone or email, read-only from chat.db, newest-first. It is clear enough to distinguish from general message search, but it does not explicitly name or contrast with siblings such as messages_search or messages_chats.

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?

Usage is only implied by 'Recent Messages by phone or email.' The description does not say when this should be used instead of messages_search, messages_chats, or message_body, and it provides no explicit exclusions or routing guidance.

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