telegram_message_reactions

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

Annotations already declare readOnly, idempotent, non-destructive, and openWorld, so the safety profile is covered. The description still adds real value beyond them: it discloses that reading marks nothing as seen and adds no reaction, and that the full reactor list is never requested with the payload signaling unavailability.

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?

Front-loaded with the core behavior, then alternatives and side-effect notes. Dense but each sentence (routing, exclusions, payload limits, no side effects) earns its place; only very minor trimming would be possible.

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?

With no output schema, the description steps in to describe return shape (per-emoji counts, attached recent reactors) and explicitly notes when data is unavailable. Combined with full parameter docs and annotations, an agent has everything needed to call and interpret it.

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% across all three parameters, and the description adds no format or syntax detail beyond what the schema already documents. Baseline 3 is appropriate when the schema carries the parameter burden.

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 ('Returns the per-emoji counts on a single message, plus... reactors') with precise scope. It distinguishes itself from the react/unreact sibling tools by name, so an agent can route correctly 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 an explicit trigger ('Use when the user asks how people reacted to one message') and explicit exclusions, naming telegram_plan_react_message, telegram_plan_unreact_message, and telegram_mentions as the correct alternatives for those cases.

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