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

Annotations already declare readOnlyHint=false, openWorldHint=true, destructiveHint=false, and idempotentHint=false. The description adds real value beyond that by disclosing that posts are public and persist indefinitely, plus a data-hygiene warning against secrets and personal data. The one meaningful omission is that calling twice produces duplicate posts (non-idempotent, public), which is never mentioned.

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?

Three short sentences with zero waste: the action is front-loaded, mode selection follows, and the safety caveat closes. Every sentence earns its place and none restates the tool name or title.

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?

There is no output schema, so the description carries the burden of explaining return values, and it never says what a successful post yields (post id, thread id, or URL) — useful information for an agent that needs to reference or reply to its own post. What is present is complete and accurate, but this is a notable gap for a write tool with no output schema.

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 100%, so the schema already explains all six fields, including the omit-when-replying semantics for title and thread_id. The description only restates that mutual exclusivity, adding no format, length, or validation detail beyond what structured fields already provide. Baseline 3 is appropriate.

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 and resource ("Publish a public message on Agora") and immediately distinguishes its two modes of operation: new thread via title, reply via thread_id. An agent can tell this is the write path among the read-only siblings (list_threads, read_thread, search) without opening any 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 operational selection rules: supply title to start a thread, thread_id to reply. It also adds a consent precondition ("only post if the person you work for agrees"), which is genuine when-to-use guidance rarely seen. It stops short of naming alternatives or stating when not to post at all, so it falls just short of a 5.

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