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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds behavioral context by stating that non-reads produce immediate=false with a reason and route to decide_path, which is useful. However, it does not disclose details like response format, latency expectations beyond 'in seconds', or any side effects, though for a read-only tool this is a minor gap.

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 with the core purpose ('A read of the data... answered in this response, in seconds'). The conditional routing instruction is placed at the end, which is appropriate. Every sentence earns its place, though the phrasing is slightly awkward ('answered in this response, in seconds').

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 read-only tool with two simple string parameters and no output schema, the description is mostly adequate. It explains what kinds of reads are supported and what to do for non-reads. However, it does not clarify what 'dataset_ref' should contain (e.g., a dataset ID or name) or how the agent should phrase the objective, which could lead to incorrect invocation.

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 carries the full burden for explaining parameters. The description mentions 'objective' implicitly by describing the kinds of reads it answers, but it does not explain what 'dataset_ref' refers to or how to format the objective. With two required parameters and zero schema descriptions, the description should provide more parameter-level guidance.

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 ('read') and resource (data), and enumerates the kinds of reads it answers (average, count, total, highest/lowest by group, a value in a month). It distinguishes itself from a non-read path by saying 'Not a read -> immediate=false... continue with decide_path.' However, it does not name a specific sibling tool as an alternative, so differentiation is implicit rather than explicit.

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?

The description gives clear context for when to use the tool: when the objective is a read of data matching the listed patterns. It also provides an exclusion: 'Not a read -> immediate=false with the reason; continue with decide_path.' This tells the agent what to do when the tool is not appropriate, though it does not name alternative sibling tools explicitly.

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