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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=false, so safety is covered. The description adds genuinely non-obvious behavior beyond that: the status is invariant across edits, approval is not granted as a side effect, a rejected post remains a draft, and a pending-approval post may only target one account. It omits side effects such as whether edits re-trigger notifications or reset approvals.

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 tight sentences, front-loaded with the editable surface and followed by the status constraints. No filler, and the most decision-relevant constraint (status never changes) is stated early.

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 a 6-parameter mutation tool with no output schema and annotations that already carry the safety profile, the description covers eligibility, field scope and key invariants well. What an agent gets back after a successful edit is left entirely implicit, though no output schema exists to offset that.

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 the baseline is 3 and the schema already documents every field, including the replace-not-append semantics of media_ids. The description adds meaning on top: the one-account ceiling for posts awaiting approval constrains profile_ids in a way no schema field states.

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 states a specific verb (change) plus the resource (a post that has not published yet) and enumerates the editable fields: caption, publish time, target accounts, attached media. It also pins the eligible statuses (scheduled, pending_approval, draft), which separates it cleanly from sprkly_schedule_post, sprkly_delete_scheduled_post and sprkly_request_post_approval.

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?

It gives clear eligibility conditions and explicitly distinguishes the edit path from the approval path ('editing a post that waits for approval does not approve it'), which is real routing guidance. It never names a sibling tool directly and gives no explicit when-not-to-use beyond the 'not published yet' gate, so it stops short of 5.

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