Get Data Updates

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

readOnlyHint=true already signals this is a safe read, so the bar is lower, and the description still adds genuinely useful behavior: the time range filters on ingestion/sync time, not record timestamps, with a concrete example ('last night's sleep records typically arrive this morning'). That non-obvious semantic would be easy to misuse without it. It says nothing about result size, pagination, or cost, so it stops short of a 5.

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?

Three sentences, front-loaded with the core purpose, then the crucial time-semantics caveat, then the follow-up instruction. No filler, no restatement of the name or title, and the most misuse-prone fact is surfaced prominently.

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?

An output schema exists, so return-value detail is correctly omitted. For a read-only, four-parameter summary tool with full schema coverage, the description supplies everything an agent needs: scope, the timing gotcha that determines correct arguments, and what to do with the result.

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 coverage is 100% (baseline 3), and the description goes beyond the schema by defining what start_time/end_time actually filter on — processing/sync time rather than record time. This is meaningful added semantics for the two required parameters, though the optional fulcra_userid and include_shared parameters are explained only in the 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?

States a specific verb and resource ('Summarize the data that arrived in the user's account during a period of time') and immediately scopes it as a discovery/changefeed tool rather than a data reader. The closing clause routes the agent to other tools for the actual changed types, so an agent can distinguish it from get_records, get_sleep, or get_time_series without opening any schema.

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?

Gives an explicit trigger ('find out what new data exists since a previous check') plus the required follow-up workflow ('then query the changed types with the appropriate tools'). It lacks explicit when-not guidance and does not name the alternative tools, leaving the agent to infer which ones qualify as 'appropriate'.

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