fitbit_sync

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

With no annotations, description fully discloses behavior: fetches from Fitbit API, stores in SQLite, incremental nature, first sync behavior. Does not hide any side effects or prerequisites.

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?

Well-structured with clear sections, but slightly verbose. Front-loaded with purpose. Could be tightened without losing clarity.

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 tool complexity (multiple data types, sync logic), description covers: purpose, usage order, parameter details, output summary, and relation to siblings. Output schema exists, so return values are documented externally.

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?

Input schema has 0% description coverage, but description adds detailed semantics for both parameters: data_types lists all options and format, days explains default and non-use after first sync. Adds significant meaning beyond schema.

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?

Description clearly states the tool syncs Fitbit data to a local cache using a specific verb ('Sync') and resource ('Fitbit health data'). It explicitly distinguishes from sibling get tools by stating 'Not for querying data - use fitbit_get_* instead.'

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?

Provides explicit guidance: 'Run this before using other fitbit_get_* tools.' Explains incremental sync behavior and when each parameter applies (first sync vs subsequent). Advises against using for queries.

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