Read one X post

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

Annotations already declare read-only/open-world/idempotent-false, but the description adds substantial context they don't carry: zero-auth, no login/cookies, a single Telos User-Agent, and explicit per-host pacing with backoff on 429/503. It also discloses the return shape ('JSON and a receipt'), which matters since there is no output 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?

Front-loaded with the triggering condition, then scope exclusion, then behavioral/network facts, then the return note. Every sentence adds a distinct fact with no filler or redundancy.

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?

Covers the essentials an agent needs: what it reads, auth posture, network/rate-limit behavior, and a brief return note. With no output schema the return description stays minimal ('JSON and a receipt'), which is a minor gap but not a blocker for a single-URL read.

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 url parameter already documents the required format ('https://x.com/<user>/status/<id>'). The description only restates that input is the post URL, adding no syntax or constraint beyond the schema, 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 and resource ('needs the text, author and date of one public X post from its URL') and names the mechanism (X's public oEmbed endpoint). The 'no search or timelines' scope line implicitly separates it from the broader telos.x.api sibling, so an agent can distinguish it without opening a schema.

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?

Front-loads a clear activation condition ('Use when an agent needs... one public X post from its URL') and gives a negative boundary ('no search or timelines'). It stops short of naming the alternative sibling (telos.x.api) explicitly, so the routing is implied rather than stated.

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