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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered structurally. The description adds genuinely useful context about how the slot is derived (channel's posting times plus already-scheduled posts), but says nothing about the return type or what happens if no slot exists.

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 and the social_post hand-off are front-loaded correctly, but the duplicated trailing 'Free. Free.' is filler that adds no information and slightly mars an otherwise tight sentence.

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?

A single-parameter tool with no output schema, so the description should signal what comes back (presumably a timestamp) — it never does, leaving the agent to guess the return shape. The usage hand-off to social_post partially compensates.

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 channel_id's provenance ('from social_channels') is documented in the schema itself. The description adds no format or constraint detail beyond the schema baseline.

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+resource: returns the next free time slot of a channel, and distinguishes itself from the sibling social_post by explaining the relationship (this feeds 'when' into that). The trailing 'Free. Free.' fragment is noise but doesn't obscure the purpose.

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?

Explicitly prescribes the downstream action: 'pass it as when to social_post', which tells an agent both when to call it and what to do with the result. No explicit exclusions or alternatives are given, keeping it below 5.

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