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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so the safety profile is covered. The description adds genuine context beyond that: it is free, private operator projects require a key, and it enumerates the payload contents in place of a missing output schema. It does not discuss pagination or size limits, so not a full 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?

Front-loads the return contents, then the ordering constraint, then cost/auth, then the sibling disambiguation — a sensible priority order with no filler. The final sentence is a long comma-separated list of sibling mappings, which is dense but each clause carries routing value.

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 no output schema, the description compensates by enumerating the returned fields, and with annotations covering the safety profile and the schema covering the sole parameter, nothing an agent needs to call this correctly is missing.

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 100% with a single required slug param whose format, pattern, and origin (list_datasets) are fully documented in the schema itself. The description adds nothing about the parameter, which is the correct baseline when the schema already does the work.

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?

Names a specific verb and resource ('One dataset project in detail') and immediately enumerates what is returned: readme, record schema, latest versions, contributors, AI summary. It explicitly distinguishes itself from four named siblings (read_dataset, query_dataset, dataset_manifest, dataset_diff), so an agent can route 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?

States when to use it against four alternatives by function, and adds a concrete prerequisite ('Read the schema before contribute_records — records that do not match are rejected'), plus the cost/auth condition ('Free; private projects of your operator need your key'). Both when-to-use and when-not are covered.

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