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

Annotations already declare readOnly/openWorld=false/idempotent/non-destructive, and the description adds genuinely new behavioral context: data is collected every 6 hours and audited before publishing, every number is {value, unit}, every record carries as_of, and no API key is needed. It does not contradict any annotation.

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-loaded with the core purpose and packed with useful detail in a few sentences. Slightly dense with parentheticals (sort list, dataset provenance), but no sentence is filler.

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?

No output schema exists, so the description must carry return-shape burden, and it partly does: it discloses that records carry {value, unit} numbers and an as_of field, plus the paging mechanism. It stops short of full field enumeration, which keeps it from a 5.

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 baseline is 3, but the description adds real meaning beyond the schema: it spells out the full sort enum including the non-obvious 'price_vs_revenue (cheapest first)', restates the 1-100/default-20 limit, and clarifies that offset pages should follow `next`.

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+resource+scope: the full ranked list of ~215 tokenized crypto apps or chains, paged. It is clearly distinguishable from siblings like gem_screener_coin (single coin) and gem_screener_picks, and names the exact source (EventTrader's Gem Screener).

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?

Explains what the tool returns (full ranked list vs. single-coin sibling), the sort modes available, and the paging contract via `next`. It also frames intent with 'A research screen, not a signal.' However, it never explicitly names an alternative tool or states when NOT to use this one.

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