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

Goes well beyond annotations (which only declare non-read-only, non-destructive, closed-world) by disclosing that the call is free, that a new brief becomes the next revision, that searches with this campaignId will rank against it thereafter, and that existing creators stay in the campaign. Those are the non-obvious side effects an agent needs before mutating live campaign data.

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?

Two sentences, front-loaded with the affected fields, then a compact block of consequences. No filler and no repetition of schema detail.

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?

Covers the mutation's side effects, cost and partial-update rule thoroughly for a 5-parameter tool with no output schema. What it omits is the response shape and any indication of validation failures, which is acceptable given no output schema is declared but leaves a small gap.

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 100%, so the baseline is 3; the description adds real semantic value by explaining that brief updates cascade into revision history and search ranking, and that unchanged fields should be omitted rather than resent. It adds no extra meaning for status or archived beyond the schema's own descriptions.

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?

Names a specific verb and resource plus the exact mutable fields (name, brief, status, archived), which cleanly separates it from create_campaign, get_campaign_status and list_campaigns. An agent knows immediately this is the partial-update path for an existing campaign.

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?

"Pass only what changes" gives the key PATCH-style usage rule that prevents accidental overwrites, and the field list implies the scope. It does not explicitly route away from siblings or state prerequisites such as needing an existing campaignId, so it falls short of an explicit when/when-not statement.

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