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

Annotations already declare readOnlyHint and openWorldHint, yet the description adds genuinely new behavior: a $0.002 USDC charge per successful call via x402 on Base/Solana/Arc, with failed calls uncharged — critical for an agent deciding whether to call. It omits latency, rate limits, and behavior for missing/redirected pages, keeping it below a 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?

Three tight sentences, zero filler: what it returns, the truncation caveat, then the price. The most decision-relevant facts (content scope and cost) are front-loaded.

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 a full schema, an output schema, and safety annotations, the description covers the remaining unknowns: source, truncation, paid access, and failure billing. Slightly short of complete because it does not say what happens when a page title does not resolve or how the payment handshake is triggered.

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% with an inline example ('The_International'), so the baseline is 3. The description adds that the page may be a tournament, team, or player page, which meaningfully widens the agent's understanding of what string to supply.

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 — returns the plain-text introduction of a single Liquipedia page — plus the exact source (public MediaWiki API) and domain (Dota 2). The scope words 'one wiki page' and 'the first section, not the full page' remove any ambiguity, and no sibling tool in the list offers wiki content.

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?

Gives clear usage boundaries: 'Dota 2 wiki only for now' and 'the intro is the first section, not the full page', telling the agent when this tool is insufficient. It stops short of naming an alternative for full-page content or for other esports titles, so the exclusions are stated without a redirect.

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