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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the safety profile is covered structurally. The description's one behavioral addition is the 'Free' tier marker, which is genuinely useful for an agent reasoning about cost/auth. It says nothing about data freshness, staleness, or whether the teaser is truncated relative to the paid brief.

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?

A single sentence with zero filler, front-loaded with the most decision-relevant token ('Free') followed by the payload contents. Nothing could be removed without losing information.

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 parameters and no output schema, the description carries the burden of describing what is returned, and it does list the three content groups. The remaining gap is relational: it never clarifies how the teaser relates to get_latest_brief or get_sample_brief, which an agent choosing among seven similar getters would need.

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?

The tool takes zero parameters, so the baseline is 4; schema coverage is 100% and there is nothing for the description to disambiguate. The description instead spends its words on return content, which is the right allocation here.

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 names a concrete content bundle (brief teaser text, Hyperliquid extreme funding at 8h-equivalent rates, BTC/ETH/SOL prices with 24h change), so an agent knows exactly what comes back. It does not, however, say how this differs from the near-identical siblings get_latest_brief or get_sample_brief, leaving the 'teaser' distinction implicit.

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 leading 'Free:' implies this is the unauthenticated/preview entry point, which is useful routing context. But there is no explicit statement of when to prefer this over get_latest_brief, get_sample_brief, or get_extreme_funding, so usage must be inferred.

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