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

Annotations already declare destructiveHint=true and openWorldHint=true, so the risk profile is largely covered structurally. The description adds the useful constraint that only scheduled posts are editable, but says nothing about irreversibility, permission requirements, or side effects of editing a scheduled post (e.g., does it re-queue or reset approval).

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?

Three short sentences, each earning its place: purpose, eligibility constraint, and update semantics. Front-loaded with the action and no 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?

For an 11-parameter mutation tool with nested objects and no output schema, the description covers the essentials (scope and partial-update behavior) but omits permissions, error conditions for non-scheduled posts, and any indication of the response. Adequate but with clear gaps given the tool's complexity.

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 parameter-level detail is already handled by the schema. The description still adds genuinely new semantics: the partial-update contract that only changed fields should be supplied, which governs how all 11 parameters are used and is not encoded in the schema itself.

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 and resource ('Update a scheduled post') that clearly separates it from siblings like create_post, delete_post, and get_post. It is clear but does not explicitly name or differentiate itself from alternatives in the tool list.

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 a hard precondition ('Only scheduled posts can be edited') and PATCH-style guidance ('Only include the fields you want to change'), which meaningfully shapes invocation. It stops short of naming alternatives (e.g., use create_post for drafts) or stating what to do when a post is not scheduled.

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