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

Annotations already declare readOnlyHint=false, openWorldHint=true, and idempotentHint=false, but the description adds the reason the tool is not read-only: it 'counts against the monthly AI allowance,' which is important cost/billing context an agent would not get from structured fields. It also explicitly states the absence of side effects ('saves nothing and schedules nothing'), which prevents an agent from assuming a plan is persisted. Non-idempotency and the external AI call are not spelled out, but the annotation already flags openWorld.

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, fully front-loaded: the first states purpose and outputs, the second states side-effect status and cost. No filler, no repetition of the title, and each clause carries distinct 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 partially compensates by enumerating the return contents (hooks, time slots, hashtags per platform). For a two-parameter, non-destructive generation tool with annotations covering openness and safety, this is nearly complete; it does not describe the structure or per-platform grouping of the result, which is the only remaining gap.

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% for both parameters (enhanced_topic with a 3–1000 char range and a reference to enhance_topic, platforms with an enum and minItems), so the schema carries the semantics. The description only restates 'a topic or brief' and 'per platform' without adding format, length, or platform-specific constraints, which matches the baseline 3 when the schema does the heavy lifting.

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 concrete verb ('suggest') and enumerates the concrete outputs (hook options, best posting time slots, trending hashtags, per platform), so an agent knows exactly what it produces. It also distinguishes itself from scheduling siblings by stating it 'saves nothing and schedules nothing.' It does not, however, differentiate itself from other ideation siblings such as get_trend_hooks or research_hashtags, which overlap on hooks and hashtags.

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?

'For a topic or brief' states the input condition for using the tool, and the clause 'saves nothing and schedules nothing' implicitly scopes it away from any persistence/publishing workflow. There is no explicit 'use X instead' routing to a named sibling, so the guidance is clear but not fully comparative.

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