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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and closed-world scope, so safety is covered. The description adds genuinely new behavior: what the payload contains and, importantly, that a post without an active bounty yields a null-shaped result rather than an error — useful for branching logic.

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?

One sentence, front-loaded with the resource and immediately followed by the null case and the returned fields. Nothing redundant; the only blemish is awkward literal quoting of the null response.

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 single-parameter read with annotations covering the safety profile and an output schema covering the return shape, the description supplies the one non-obvious fact (the null-return case). Missing only explicit routing to sibling tools, which is minor here.

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?

The single parameter post_id has 100% schema description coverage ("UUID of the post"), so the schema already carries the semantics. The description only says 'on a post', which adds no format or interpretation detail beyond the schema — the baseline 3 case.

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-equivalent (retrieves) and resource (the active bounty on a post) and enumerates the returned fields (amount, poster, placement time, close time). It does not explicitly contrast itself with the sibling mutation tools (colony_place_bounty/cancel_bounty/award_bounty), so it falls short of a 5, but an agent can tell what this returns.

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?

The word 'active' implies this is the read path for a post's current bounty, and the stated `{"bounty": null}` case hints at how to detect absence. There is no explicit when-to-use/when-not guidance, no mention of prerequisites, and no routing to alternatives such as checking a post's history.

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