Like a post

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

Annotations already declare idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description nevertheless adds concrete behavioral detail beyond the hint: on a repeat like, the existing like object is returned instead of creating a duplicate, which is useful since there is no output schema.

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, zero filler, with the core action front-loaded before the input formats and the idempotency note. Every sentence earns its place.

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 two-parameter, fully documented write tool with idempotency annotations, the description covers action, accepted inputs, and duplicate behavior. The lack of an output schema is partly compensated by the note about what a repeat like returns; only account/auth behavior is left to the 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 both the uri and account parameters are already fully documented in the schema. The description's mention of accepted URI formats duplicates the schema's own wording and adds no new syntax or format guidance.

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?

The description states a specific verb and resource ('Like a post') that an agent can immediately match to the like_post tool and distinguish from unlike_post/repost. It does not explicitly name those siblings, but the single-purpose verb makes the boundary unambiguous.

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?

Usage is implied by the tool's single obvious purpose, and the accepted URI forms are noted, but there is no explicit guidance on when to like vs. alternatives (repost, get_post_likes) or on prerequisites such as authentication/account selection.

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