sync_imessage

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

With no annotations provided, the description carries the full behavioral burden and does so well: it discloses read-only access, platform restriction ('returns an error dict on other platforms without raising'), the Full Disk Access prerequisite, and the IMESSAGE_DB_PATH override. It omits idempotency/incremental behavior and whether existing synced data is replaced, which for a sync tool would matter.

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?

Front-loaded with the core purpose, then platform/prerequisite details, then the argument. Every sentence carries information, though the Full Disk Access sentence is somewhat long and the parenthetical remediation command is more operational than agent-facing.

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?

For a single-optional-param tool with no output schema, the definition covers platform, prerequisites, path override, and filter semantics adequately. The return shape is only hinted at ('error dict'), so an agent has a mild gap on what a successful sync produces, but nothing critical is missing.

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 compensate, and it does: chat_name is explained as an optional filter matching against chat_identifier (with the '+1234567890' example) or display name. This adds real matching semantics the bare 'Chat Name' property name does not convey.

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 ('Sync iMessage/SMS conversations from the local macOS Messages database') and names the exact data source (chat.db). It clearly distinguishes itself from siblings like sync_signal, sync_telegram, and import_sms_backup by anchoring to the local macOS Messages store rather than another provider or an import path.

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?

It gives clear operational context: macOS-only, read-only, and the Full Disk Access requirement with a concrete remediation command. It does not, however, tell the agent when to prefer this over sync_all or import_sms_backup, so the alternative-selection guidance is implied rather than stated.

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