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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description is consistent ('Read-only'). Beyond that it discloses what each result contains — a plain-language sentence, canMerge and canArm flags, the merge/arm endpoints, plus the separate `waiting_on_you` and `not_ready` groupings — which is real behavioral payload an agent cannot get from the annotations or schema.

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?

The eligibility test is front-loaded and the matching is precise, so most clauses earn their place in a dense single paragraph. It is long and clause-heavy, and the parenthetical about the merge gate's own conflict probe plus the trailing 'Read-only' repeat what annotations already convey.

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?

No output schema exists, yet the description covers the return shape (readiness sentence, canMerge/canArm, endpoints, waiting_on_you, not_ready), the scope semantics of all three optional params, and the read-only safety profile. Nothing an agent needs in order to call this correctly is missing.

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%, so the baseline is 3, but the description adds genuine meaning by explaining how the optional parameters combine into three distinct scopes rather than just listing them. It stops short of stating edge cases (e.g. owner supplied without repo), so it is above baseline but not exhaustive.

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 resource (open pull requests) plus an enumerated, unambiguous predicate: not a draft, CI green at head, no gate failing or running, no standing change request, branch protection satisfied, no conflicts, auto-merge not armed. It also implicitly separates itself from merjax_list_prs by noting that `not_ready` carries the remaining open PRs with their first blocking reason.

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?

Scope selection is spelled out explicitly (owner+repo = one repository, org = whole organisation, neither = everything you can merge in), and the follow-up actions are named: merjax_set_auto_merge to arm, merjax_merge_pr to merge. It never explicitly says when to prefer merjax_list_prs or merjax_pr_status_summary instead, so the exclusion side of the guidance is missing.

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