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

Annotations already declare the mutation profile (readOnlyHint=false, destructiveHint=true, openWorldHint=false), so the description's job is narrower. It still adds real value by disclosing the post-condition — the run resumes — which annotations cannot express. It omits reversibility, staleness/error behavior, and any permission requirements, keeping it short of a 5.

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 front-loaded sentence pairing the action with its effect. No filler, no restatement of the title, and the behavioral consequence is placed where it will be read first.

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?

An output schema exists, so return values need not be explained, and the one parameter is fully covered. Still, for a destructive mutation it should say more about failure modes — already-resolved approvals, whether the rejection is reversible, and who can reject — leaving it adequate but with clear gaps.

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% and the single messageId parameter is already documented in the schema, including its source (ranla_list_approvals or a pendingApproval result). The description adds no format, validation, or sourcing detail beyond that, so the baseline 3 applies.

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 ('Reject') and a specific resource ('a pending Ranla approval'), plus the condition under which rejection is valid. It implicitly contrasts with the sibling ranla_approve, but never names it, so an agent must infer the pairing rather than being told.

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 word 'pending' supplies the precondition for use, implying the agent must have an unresolved approval (obtained via ranla_list_approvals/ranla_get_thread). However, there is no explicit when-not guidance, no mention of the approve alternative, and no statement about what happens if the approval is already resolved or expired.

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