editMessageReplyMarkup

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

With no annotations, the description must carry behavioral disclosure. It does disclose the operation ('edit only reply markup') and the return behavior (edited Message or True for inline messages), but it does not mention permission requirements, the effect of passing an empty reply_markup (removing the keyboard), or reversibility.

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 compact sentence front-loads the action and scope, then gives the return behavior. Every clause contributes essential information with no redundancy.

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?

The description covers the tool's purpose and return values, which is needed since there is no output schema. Conditional parameter requirements and inline_message_id semantics are already described in the schema, so the main gap is the lack of explicit alternative routing, which is minor.

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 schema already provides full descriptions for all 5 parameters (100% coverage), so the baseline is 3. The description adds no parameter-level detail beyond 'reply markup' and return behavior, which do not enhance the schema's parameter information.

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 uses a specific verb ('Edit') and precise resource ('reply markup of messages'), and the word 'only' explicitly narrows scope from sibling edit tools like editMessageText and editMessageCaption. This makes the tool's role 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?

The limitation 'only the reply markup' implicitly tells the agent to choose this tool when just the inline keyboard needs changing, not text/caption/media. However, it does not explicitly name alternatives or state when not to use it, so the guidance is clear but not exhaustive.

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