fc update comment

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

Annotations already declare destructiveHint=true and idempotentHint=false, but the description adds real value beyond them: it discloses that media is reconciled against the submitted list (i.e. attachments can be dropped), that hooks/announcements/automations can affect other people, and that no retries are permitted. It stops short of saying exactly what happens to media omitted from the list.

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 purpose is front-loaded in the first sentence and the operational caveats follow compactly. The controller/route-source metadata is arguably filler for an agent, but it is brief and does not bury the important 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?

For a destructive 7-parameter mutation with a nested payload object and no output schema, the description covers the key behavioral risks (confirmation requirement, side effects, no retries, media reconciliation). It could still clarify how the top-level comment, payload, and payload_file variants relate, but the schema covers those at 86%.

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 86%, so the schema already documents account, confirm, feed_id, comment_id, payload and payload_file. The description's mention of a 'submitted list' of media does not map to any visible parameter, adding little semantic detail beyond what the schema supplies. Baseline 3 is appropriate.

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 (Replaces) and resource (body of an existing comment) plus secondary effects (re-render, media reconciliation). This clearly distinguishes it from the sibling fc_create_comment and fc_delete_comment operations.

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 description states a precondition ('Explicit local confirmation is required') and warns of downstream side effects, which implies when this is safe to call. However it never states when to use this vs. alternatives or when not to use it, leaving the routing decision to be inferred from the name.

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