Get historical values

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

No annotations are provided, so description carries full burden. It discloses time format flexibility and aggregation behavior but does not declare that the operation is read-only, nor mention any destructive effects, rate limits, or authorization needs. Lacks explicit safety traits.

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 sentences efficiently convey purpose and key parameter guidance. Front-loaded with the core task, then additional details about time formats and aggregation. No extraneous text.

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?

Tool has 6 parameters (2 required) and no output schema. Description covers time handling and aggregation, which are the main complexities. However, it does not describe the return format (e.g., array of values with timestamps) or pagination. Still, it is sufficient for an agent to use the tool correctly.

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%, so baseline is 3. Description adds value by explaining accepted time formats (RFC 3339, relative durations, 'now', etc.) and providing usage context for aggregation and bucket parameters beyond schema descriptions. This helps an agent correctly format requests.

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 'Historical values over a time range with optional server-side aggregation', specifying both the verb (get) and resource (historical values). This distinguishes it from sibling tools like read_current_value (present value) and get_object (object metadata).

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?

Description implicitly suggests when to use aggregation ('For long ranges use aggregation...'), but does not explicitly contrast with sibling tools like read_current_value or get_object for simpler queries. No when-not-to-use guidance is provided.

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