Check if an address is subscribed to a specific publisher on PayPerByte.
| Name | Required | Description | Default |
|---|---|---|---|
| publisher | Yes | Publisher Ethereum address (0x...) | |
| subscriber | Yes | Subscriber Ethereum address (0x...) |
| Name | Required | Description | Default |
|---|---|---|---|
| subscribed | Yes | True if the subscriber has an active subscription to the publisher |
Changes observed during successful MCP inspections. Dates show when Glama detected each change.
Output schema / (root)Previous value: -nullNew value: +{
+ "$schema": "http://json-schema.org/draft-07/schema#",
+ "additionalProperties": false,
+ "properties": {
+ "subscribed": {
+ "description": "True if the subscriber has an active subscription to the publisher",
+ "type": "boolean"
+ }
+ },
+ "required": [
+ "subscribed"
+ ],
+ "type": "object"
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The annotations already declare the tool as readOnlyHint, idempotentHint, and non-destructive. The description is consistent with these, but it adds no extra behavioral context beyond what annotations and schema already imply. For a simple read-only check, this is sufficient.
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 description is a single sentence, front-loaded with the action verb and key objects. It communicates the essential purpose without any unnecessary words or repetition.
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?
This is a simple read-only tool with two fully documented parameters, clear annotations, and an output schema. The description, combined with the schema and annotations, provides all necessary information for an agent to correctly invoke the tool.
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 input schema provides full descriptions for both parameters (subscriber and publisher) as Ethereum addresses, with 100% coverage. The description does not add further semantic detail, so it relies on the schema, which is adequate.
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?
The description clearly states the action ('Check if') and the exact resources involved ('an address', 'a specific publisher', 'subscription'). It distinguishes itself from sibling tools like byte_subscribe (creation) and byte_list_my_subscriptions (listing own subscriptions).
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 implies the use case: verifying a specific subscriber-publisher pair. However, it does not explicitly mention when to prefer this over alternatives like byte_subscription_health or byte_list_my_subscriptions, and offers no exclusions or prerequisites.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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Each tool targets a distinct action or resource, and overlapping functions (buy_data vs subscribe, check_subscription vs list_my_subscriptions) are explicitly differentiated in descriptions. No two tools appear to do the same thing.
Most tools follow the byte_verb_noun pattern (e.g., byte_buy_data, byte_get_publisher), but a few deviate: byte_subscription_health uses a noun phrase, and byte_unsubscribe lacks an explicit object. The consistent byte_ prefix keeps the set recognizable.
15 tools is at the upper edge of the well-scoped range, and each tool serves a distinct purpose within the PayPerByte protocol—discovery, purchasing, publishing, verification, and account management. No redundant or filler tools.
Core lifecycle coverage is strong: list/search, subscribe/unsubscribe, buy, publish, register, verify, health, and network stats. Minor gaps exist, such as no explicit tool to fetch historical streamed messages or update a publisher schema, but these are workable.