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 adds the valuable behavioral facts: this is a free tier capped at 10 rows, sourced from SEC filings, and the exact capability gap versus the paid tool. It doesn't mention data freshness or update cadence, which is the remaining useful detail for a filings-derived dataset.

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 with zero waste: the free-tier signal is front-loaded, the scope follows, and the upsell path closes it. Every clause carries information an agent needs to choose or skip the tool.

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 no-parameter, no-output-schema listing tool the description covers source, scope, tier and upgrade path, which is close to sufficient. It could still say roughly what each row contains (company, ticker, holdings value) to set expectations for the return.

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 there is nothing to disambiguate and the baseline is 4. The description adds nothing spurious on this axis.

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 resource (Top 10 SEC-reporting companies by crypto treasury value) with the underlying source (SEC filings) and enumerates what counts as a crypto treasury (corporate bitcoin holdings, ETH/SOL treasury companies, miners). It explicitly distinguishes itself from the paid sibling crypto_treasuries.

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 'FREE' prefix plus the note that crypto_treasuries ($0.005) 'adds every company, cost basis, filing links and per-asset totals' gives a clear free-vs-paid routing rule. It stops short of explicitly saying when not to use it (e.g., versus the similarly named free_crypto_top10), so it's a clear context rather than a full when/when-not rule set.

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