validate_post

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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false, but the description goes further by enumerating the specific side effects that do NOT occur (no records, no media copy, no post-item or storage quota, no X quota reservation, no webhooks, no publication enqueue). It also discloses a real failure mode beyond annotations: third-party media may return remote_media_not_materialized because live create performs the storage copy and byte validation. Nothing contradicts the annotations.

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?

Purpose is front-loaded in the first clause, followed by side-effect exclusions, then the media caveat, then the usage instruction. Every sentence carries information, but the six-item negation list is dense enough that it reads as a run-on.

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 12-parameter validator with nested per-platform settings and no output schema, the description covers side effects and workflow well but says nothing about what validation returns — errors vs. warnings, whether a normalized payload comes back, or which field failures are blocking. An agent can decide to call it, but not interpret its result.

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% across all 12 parameters (including deep nested platform_settings and instagram_settings), so the schema already carries parameter meaning and the baseline is 3. The description adds only indirect param context via the third-party media caveat, which explains why media_url/media_urls behave differently here than in create_post; it does not document caption, thread_posts, or scheduling semantics beyond the schema.

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?

"Validate and normalize one post without creating it" gives a specific verb pair (validate/normalize), a specific resource (one post), and a scope boundary (no creation). This immediately separates it from create_post, create_posts_batch, and update_post without the agent needing to inspect schemas.

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?

"Use this before showing the final preview and asking for confirmation to call create_post" names the alternative tool and the exact workflow condition that selects it. The ordering constraint (validate → preview → confirm → create) is explicit rather than inferred.

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