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

Annotations only carry readOnlyHint=false and openWorldHint=true; the description adds genuine value beyond these. The 'text-only check of an unrecorded script' and 'maps relative attention risk... does not measure or predict published retention, cannot account for delivery, editing, thumbnail, topic or distribution' disclosures clarify what the tool will and won't report. The one gap: the schema's email/quota mechanics (free daily check, then email required) are not explained in the description, leaving an operational behavior undocumented. No contradiction with annotations.

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?

Lengthy but densely informative — every clause earns its place. The first sentence front-loads purpose with specifics, the second gives usage guidance, and the closing sentences cover scope disclaimers. It could be slightly tighter (the 'Could not account for...' list repeats the thrust of 'does not measure retention'), but nothing 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?

With no output schema, the description carries the burden of describing return values, and it does: attention pull per sentence, curiosity gap, payoff distance, top issues, and rewritten alternatives. Combined with explicit scope limitations and usage routing, an agent has everything needed to invoke it correctly. Only the email/quota operation is externalized, and the schema handles that.

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 the baseline is 3 and the schema already documents all three parameters fully (email's conditionality, niche's optionality, hook_text's format and length). The description reinforces hook_text via 'hook or opening paragraph' but adds no parameter semantics beyond what the schema supplies. It correctly meets the baseline without exceeding it.

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 (score), resource (opening lines of a YouTube script), and enumerates the concrete outputs: per-sentence attention pull, curiosity gap, payoff distance, top issues, and rewritten alternatives. It further carves out its exact scope relative to audit_script, so an agent can distinguish them without inspecting other schemas.

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 explicit when-to-use conditions ('shares only a hook or opening paragraph', 'wants a fast second opinion'), names the alternative tool audit_script directly, and frames the tradeoff ('Cheaper and narrower'). The scope exclusions (doesn't measure retention, can't see delivery/editing/thumbnail) also steer an agent away from misapplying it.

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