DYOE Page Metadata ($0.01)

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

Annotations already declare readOnlyHint and openWorldHint, so safety profile is covered. The description adds genuinely useful context beyond that: the exact cost ($0.01 USDC on Base) and the payment mechanism (x402), which an agent needs before calling. It stops short of disclosing failure/rate-limit 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 compact sentences that front-load the extraction purpose before the cost. The 'Input: ?url=' fragment is mildly redundant given the schema, but overall the text is tight and waste-free.

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 single-parameter read tool with annotations covering safety and no output schema, the description supplies the missing operational piece (cost/payment) and the returned-field list. Nothing critical for correct invocation is absent, though it never clarifies return shape or error handling.

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% and the schema already documents the single url parameter with an example, so the schema carries the burden. The description's 'Input: ?url=' merely restates the parameter name without adding format or edge-case meaning. Baseline 3 is correct.

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 (Extract) plus the exact resource fields (title, description, OpenGraph image, favicon, canonical) and the input domain (any URL). This is far more specific than the sibling tools and lets an agent distinguish it from dyoe_extract or dyoe_intel 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?

Names intended use cases ('link previews & summaries'), which implies when to reach for it. However it never states when NOT to use it or points to an alternative sibling (e.g. dyoe_extract), so the routing guidance is only implied.

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