mark_agent_message_failed

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

Describes all automatic actions: sets completed_at, status to 'failed', records error, updates delivery status. Also mentions error case (422) if no active attempt. With no annotations, this is thorough.

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?

Concise, well-structured: purpose sentence, usage instruction, bullet list of automatic actions, prerequisite note, and clear parameter descriptions. No extraneous content.

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?

Fully covers the operation: explains what it does, prerequisites, parameters, and return value. References sibling tools. Complete for a simple mutation tool with 3 required params.

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 description adds meaning beyond schema: explains each parameter (chat_id, message_id, error) is required and provides brief rationale. Despite 0% schema coverage, the description compensates adequately.

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 clearly states the verb and resource: 'Mark a message processing as failed by the agent.' It distinguishes from sibling tools like 'mark_agent_message_processing' and 'mark_agent_message_processed' by contrasting when to call each.

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?

Explicitly says when to use: 'Call this when the agent cannot process a message.' Also provides a prerequisite: requires an active processing attempt, and directs to call 'mark_agent_message_processing' first if not.

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