get_platform_rules

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world). The description goes further by enumerating what data the agent will actually receive, including concrete examples of required fields per platform, which is real added context.

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?

The content-rich clause is front-loaded and the usage instruction trails it, which is the right order. It is list-heavy but each enumerated category (limits, media rules, required fields, features) earns its place.

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 returns, and it does so at a useful level of abstraction with concrete examples. Nothing critical about calling the tool correctly is missing.

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% and the single optional param is fully documented there. The description repeats the 'leave it out for all platforms' semantics and adds example values, but contributes nothing 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?

The description names a specific resource and its contents: platform posting constraints (text limits, media rules, required fields, features). It is unmistakably distinct from every sibling, none of which returns platform policy data.

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 framing 'What a platform accepts BEFORE you post' establishes when this is useful (pre-flight validation against a channel), and the closing sentence explains how to scope the lookup. It stops short of explicitly contrasting with siblings, though no sibling overlaps.

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