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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered; the description adds genuinely new behavior: the upstream source (the NRL site's own ladder data) and the billing model ($0.002 USDC per successful call via x402 on Base, Solana or Arc, failures not charged). That cost/auth disclosure is exactly the kind of context annotations cannot carry. It stops short of describing data freshness or update cadence, which matters for an open-world scraped source.

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 resource and its scope, then fields, then exclusions, then alternatives, then price — a sensible order. The field enumeration is long and partly duplicates the output schema, and the two named alternatives (FPL, MLB) are only loosely related to an NRL ladder tool, so some text is lower value than it appears.

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 one-parameter read tool with full schema coverage, an output schema, and readOnly annotations, the definition covers purpose, scope exclusion, cost, and alternatives. The remaining gap is freshness/update timing of the ladder data, which is meaningful for an open-world scraped endpoint but not strictly required to invoke correctly.

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 optional 'season' parameter whose range (2000–2026) and default (2026) are documented in the schema. The description only implies the season dimension via 'for a season' and adds no format or edge-case guidance beyond the schema, so the baseline of 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: the NRL Telstra Premiership ladder for a given season, sourced from the NRL site's own ladder data. It enumerates the returned fields (position, club, played, wins, draws, losses, for/against, points difference, competition points, form, streak) and explicitly bounds scope with 'Season stats only; no player stats', so an agent can separate it from player-stat siblings without opening a 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?

The description gives a clear usage boundary ('Season stats only; no player stats') and routes two adjacent needs elsewhere (dev_fpl_premier_league for FPL player stats, dev_mlb_stats for MLB player stats). It does not address the more plausible alternatives on this server, such as dev_espn_standings or dev_sporting_life_racing, so sibling selection for other ladder/standings sources is left to inference.

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