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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the mutation risk is known. The description goes substantially beyond them: it documents the before/would_set/verified readback, the dry-run mode via validate_only, the exact error codes and the DRAFT exception, timezone semantics (00:00 UTC start, 23:59:59 UTC end), and that unset fields are preserved.

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?

Purpose is front-loaded in the first clause and nearly every sentence carries operational detail. It is dense and semicolon-heavy rather than bulleted, which makes it harder to scan for an agent parsing parameters, but nothing is wasted.

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?

An output schema exists, so return values need not be explained, and the description still notes the before/after/verified shape. For a destructive mutation with 6 parameters it covers edge cases, dry-run behavior, timezone and field-preservation rules — nothing an agent needs 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 description coverage is 0%, so the description must carry the burden — and it does. It defines start_date (first active day), end_date (last active day, inclusive, 'YYYY-MM-DD' UTC), remove_end (unbounded runtime), validate_only (read-only preview) and workspace (optional when a single workspace exists), adding format and behavior the schema lacks.

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: change the runtime/schedule of a LinkedIn campaign and read it back (before/after/verified). It also distinguishes itself from linkedin_create_campaign, which sets the runtime at creation time, so the agent can tell the two apart without opening the schemas.

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 concrete conditions: remove_end=True makes the campaign run indefinitely, validate_only=True previews without writing, and linkedin_create_campaign is the path for setting runtime at creation. It also flags when-not cases — a new start in the past errors (start_in_past) and a new start after the previous one has passed is rejected (start_immutable) unless the campaign is DRAFT.

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