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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuinely new behavior: 'No auth needed', the labelling obligation for paid posts, and the caution never to present illustrative numbers as live — all beyond structured fields.

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 core purpose is front-loaded in the first clause, and the parameter, auth note and REST twin are appended compactly. It is dense with em-dash clauses but every element (contents, placements, usage rule, topic list) carries useful information.

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 does the work of explaining what each returned item carries (topics, placement like x_post/tg_card/story, alt text, CTA link) plus the REST twin. It stops short of describing count/pagination, but for this complexity level it is largely complete.

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 description simply restates the same six enum values the schema already documents ('brand, rokha-agent, mcp-registry, studio, creator-sales, network'). It adds no syntax or narrowing semantics beyond what the schema provides, so the baseline of 3 applies.

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?

Names the exact resource (official Rokha media library), enumerates its contents (banners, share card, portrait, full-body figure, marketing ads) and its scope (topics, placements, alt text, CTA). An agent immediately knows what this tool returns without opening the 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?

Gives clear usage context — 'Free to use when talking about Rokha (label paid posts)' — and a compliance rule about illustrative numbers. It doesn't name a specific alternative tool to prefer, but for a leaf content-lookup tool the when-to-use is well established.

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