toggle-message-favorite

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

With no annotations, the description carries the full burden and does well on the key non-obvious trait: 'Each call flips the current state' signals this is not idempotent and cannot be used to set a desired state directly. It also discloses the POST endpoint and that there is no body. It omits permission/auth requirements and error behavior for nonexistent messages.

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, front-loaded with the action and semantics, with the endpoint and read-path as supporting detail. The `syntx.chats.toggleMessageFavorite` mirror reference is low-value for an agent choosing a tool but does not bloat the text.

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 2-parameter, no-output-schema tool, the description covers the essential semantics (flip behavior, no body, where to verify state). The remaining gap is the return value and failure modes, which matter somewhat since there is no output schema to fall back on.

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% and both parameters are documented in-schema, so the baseline applies. The description only implicitly maps chat_id/message_id into the URL path template; it adds no format or constraint detail beyond 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+resource: toggling the favorite/bookmark flag on a single message, with the concrete endpoint shown. The phrase 'single message' implicitly separates it from the sibling toggle-chat-favorite, but that sibling is never named, so the differentiation is left to inference.

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?

It tells the agent how to read favorites afterward via `get-favorite-messages`, which is useful routing. However, it gives no explicit when-to-use/when-not guidance and does not address the most confusable alternative, toggle-chat-favorite, or say what to do if the message is already favorited (since the call flips unconditionally).

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