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

Beyond the annotations' safety profile, it discloses exactly what is preserved (caption, media, destinations), two hard exclusions (drafts, published), a credential-mode edge case, and two authorization prerequisites (access to every destination, owner's subscription allowance). This is rich behavioral context an agent cannot get from the schema or hints.

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 short sentences, each carrying distinct information (action, preservation, exclusions, prerequisites), with the core action front-loaded and no redundant 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 a 2-parameter mutation with no output schema, the description covers what changes, what stays the same, what is blocked, and what authorization is needed. Nothing an agent needs to decide whether and how to call it is missing.

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 coverage is 50%: scheduledAt is documented in the schema, postId is not documented anywhere, and the description's 'future ISO 8601 time' requirement simply restates the schema text. Baseline 3 is appropriate since the schema carries the parameter detail and the description adds no new syntax or constraint.

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 opens with a specific verb+resource+scope: 'Moves an existing scheduled post to a future ISO 8601 time.' This clearly separates it from siblings like update_post (edits content), cancel_post (removes), and create_post (creates new).

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 states clear eligibility conditions: drafts and published posts cannot be rescheduled, and review-mode credentials block the move. It stops short of naming an alternative path (e.g., cancel_post + create_post) for when the tool cannot be used, so it is strong context without explicit routing.

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