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

Annotations already declare it a safe idempotent read, so the description spends its budget on substance: it describes the per-template payload (key, what it does, keyword/link requirement, availability, why_not), and it explains the instagram_only semantics for follow_check/tap_to_unlock, including the constraint that a follow check cannot run on a Facebook Page. That is real behavioral context an agent cannot infer from 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 opening clause is well front-loaded, but the rest is a single dense run-on packing several ideas (instagram_only semantics, the X public-reply vs DM distinction) into comma-chained clauses that are hard to parse. The trailing 'x_comment_reply ... With dms it sends one DM instead' is cryptic without surrounding context and does little to help selection.

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?

For a zero-parameter read with an output schema, this covers the important ground: what is listed, what each entry carries, the availability/why_not signal, the Instagram-only caveat, and the handoff to create_automation. Only the ambiguous closing sentence about X replies leaves a reader unsure what it is describing.

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 tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline of 4 applies. The mentions of follow_check, tap_to_unlock and instagram_only describe returned fields rather than inputs, which is useful but not a parameter concern.

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?

Names a specific verb and resource ('Lists the ready-made Instagram DM automations Postkey can build') and immediately enumerates the template families (comment-to-DM, follow to unlock, email capture, keyword replies, story replies). It explicitly separates itself from the most confusable sibling by noting that the profile's existing automations live in postkey_list_automations.

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 a clear next-step contract: 'Use a key with postkey_create_automation', which tells the agent this is a discovery step in a create flow, and it routes to postkey_list_automations for already-installed automations. It stops short of covering the other similarly named template lister (postkey_x_list_templates) or saying when not to call this.

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