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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description goes beyond that with real behavioral constraints: headline medians/quartiles appear only with ≥3 comparable priced members and monthly/per-seat/per-call prices are never blended, which tells the agent what results can look like and why.

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 report contents are front-loaded in a single dense sentence, followed by the argument instruction. Efficient overall, though the final sentence largely repeats the benchmark_id guidance already present in the schema.

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?

With an output schema present, return-structure detail is unnecessary and annotations carry the safety profile. The description supplies the one non-obvious caveat (aggregation threshold) and covers the read path adequately for a 4-parameter tool.

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 as_of, version, benchmark_id, and response_mode are already documented, including the enum. The description only reinforces that benchmark_id is a cb_ token passed as an argument, adding little beyond the schema; baseline 3 applies.

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 ('Get a private custom benchmark's current report') and enumerates what the report contains: members, stats, cohorts, historical index, coverage. This clearly separates it from the create/update/delete_custom_benchmark siblings and from market-level tools like get_price_index.

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?

Usage is implied — read the report for a custom benchmark you already own — but there is no explicit when-to-use or when-not versus siblings such as price_benchmark, compare_providers, or get_price_index. The only explicit instruction is passing benchmark_id as an argument.

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