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

Beyond the annotations (readOnlyHint=false, destructiveHint=true), the description discloses non-obvious behavior: supplied fields are overwritten, publication is re-enqueued, approval gating can suppress the re-enqueue, and completed posts are immutable. The retry-safe claim is a nuance versus idempotentHint=false, but since idempotency_key is a required argument, the description is describing reuse of the same arguments rather than a tool-level misleading claim; still worth reconciling.

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?

Four tight sentences with zero filler: purpose first, then updatable fields, then side effects and constraints, then retry behavior. The most decision-relevant facts (mutability and overwrite semantics) are front-loaded.

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 mutating tool whose annotations already declare destructive/openWorld and which has no output schema, this covers the essential gaps: what gets overwritten, what side effect occurs, what is forbidden, and retry semantics. Remaining gaps (pagination/return shape, scoping parameters) are minor for an update-by-id operation.

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 only 50%, so the description must carry weight: it names the updatable fields (content, scheduled_at, timezone, metadata) and explains idempotency_key's retry semantics, which the schema only constrains by pattern. However, it says nothing about brand_id or workspace_id (the schema notes workspace_id is required for content creation), leaving part of the gap unfilled.

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 first sentence names a specific verb and resource with a scope qualifier ('existing mutable scheduled post'), so an agent knows exactly what is mutated. It stops short of differentiating itself from the very similar sibling aidelly_update_scheduled_post (and aidelly_update_draft), so sibling routing still requires schema inspection.

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 real usage conditions: the post must be mutable, 'completed posts cannot be edited', re-publication happens 'unless approval is required', and retries are safe with the same idempotency_key. It never names an alternative tool to use instead when the target is completed or when a non-scheduled post is meant, so the exclusion is stated without an exit path.

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