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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description correctly adds the non-obvious behavioral fact: this is a paid call at $0.01 USDC on Base via x402 at POST /v1/hook/score. Cost and payment rail are exactly the kind of context annotations can't carry; it doesn't cover latency or failure/refund behavior.

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 filler: the usage condition is front-loaded and the payment mechanics follow. Nothing is repeated from the name or schema.

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 simple 2-param scoring tool with a 0-100 output range stated in the description and safety covered by annotations, an agent has what it needs to call it. The only gap is what the score response actually contains beyond the number, though no output schema exists to cover it.

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%, so both parameters (headline, platform) are already documented, establishing the baseline 3. The description adds no meaning about parameter defaults or valid platform values beyond the schema.

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 ('scored 0-100') plus the scoring rubric ('369 team's hook rules'), and limits scope to gaming headlines, which cleanly separates it from siblings like game_facts or text_analyze.

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?

'Use this when you need a gaming headline or hook scored' gives a clear triggering condition. It doesn't name alternatives or state when not to use it, but the niche is narrow enough that little inference is required.

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