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

No annotations are supplied, so the description carries the full burden. It says nothing about whether hearting is idempotent or toggling, whether it requires authentication or ownership, whether it is reversible, or what happens on failure.

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?

A single short sentence with the action front-loaded and no filler. It is economical, though its brevity reflects under-specification as much as efficiency.

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 mutation tool with no annotations, no output schema, and an undocumented required parameter, the description is far too thin. It does not tell the agent what a successful heart does to the note, whether it can be undone, or how to supply note_id.

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 0% and the description never mentions the single required note_id parameter, its format (a max-32-char string), or where the agent should obtain it. The one parameter is left entirely unexplained by both schema and description.

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 concrete verb ('Add a heart') and resource ('note'), making the action unambiguous. The siblings (leave_note, read_notes) are semantically distinct enough that the agent can route correctly, though the description never explicitly distinguishes itself from them.

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 phrase 'a note you liked' gives a soft contextual cue for when this applies, but there is no explicit when-to-use, when-not-to-use, or comparison against leave_note/read_notes. Usage is implied rather than stated.

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