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

Goes well beyond the annotations (readOnlyHint=false, destructiveHint=false): it discloses auth prerequisites, eligibility rules (post after campaign start, must quote/reply/link official post or carry a ref link), rate limits (one per minute, 20 per campaign), replacement semantics, and the exact refusal codes. This is a mutation tool and the description fully accounts for its side effects.

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?

Front-loads prerequisites first, then the submission rule, then limits, refusals, and return shape. Dense parenthetical clauses make it slightly heavy to parse, but nearly every sentence carries load-bearing constraint information.

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?

Even without an output schema, the description names the return shape ({ok, points, share_link}), specifies all prerequisites, eligibility constraints, rate limits, and the full refusal taxonomy. Nothing an agent needs to call this correctly 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 100%, so baseline is 3, but the description adds meaning beyond the schema: `post_url` must be the caller's own post made by the linked X account and after campaign start, and ties `campaign_id` to the `campaigns` tool. This is genuinely useful disambiguation, though the core format detail is already in the schema.

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 (submit) and resource (one post of your own backing a live support campaign), and disambiguates from the nearby `campaigns` tool by pointing at it for the campaign_id. An agent can distinguish this from amplify_campaigns or party_proof without opening a schema.

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 clear preconditions (JWT, claimed page, linked X account) and routing context (campaign_id from `campaigns`), plus the resubmission rule. It stops short of explicitly naming an alternative to use when these conditions fail, but the requirements themselves are precisely stated.

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