Head to head · Phone numbers · October 2026 research run

didlogic Voice API vs Telnyx Voice API + MCP

Telnyx Voice API + MCP scores 74.3 (BB) on agent readiness against didlogic Voice API's 49.8 (D), and leads in 6 of 7 scored categories. Both do phone numbers. Telnyx Voice API + MCP is cheaper for phone numbers, $1 against $2 per month (plan).

Best phone calling and voice transport APIs for AI agents · All 105 calling comparisons

Which one, for what

didlogic Voice API D

Best for Teams that need numbers and SIP termination in many countries and a WebSocket bridge to a voice agent.

Also in its favour

  • Free to start without a card

Watch for

No status page or incident history found

Telnyx Voice API + MCP BB

Best for Cost-sensitive US outbound voice agents and for agents that must onboard and pay without a person.

Ahead on

  • Reliability, 75 against 26
  • Schema & documentation, 93 against 87
  • Agent ergonomics, 90 against 57
  • Payments & pricing, 65 against 38
  • Maintenance & community, 83 against 38
  • Transparency & trust, 72 against 58

Also in its favour

  • Cheaper for phone numbers, $1 against $2 per month (plan)
  • Agent-ready, a grade of BB or better
  • Runs on your own machine

Watch for

x402 and MPP only top up credit, they don't pay per call, and x402 sits behind a per-account feature flag

Why the edge

Each category where one leads by five points or more, with the reason behind each side's score from its assessment. The numbers are in the table below; this is what they stand for.

Reliability Telnyx Voice API + MCP +49

didlogic Voice API 26

Graded on the hosted API and MCP server with the hosted lines. The footer's network status page carries no components or incidents, and no other status page was found (0). No readable incident history (5). Rate limits are given only for recording lookups (one a second, one lookup a minute) (5 of 15). Those endpoints document 429 with Retry-After and X-RateLimit headers, with no backoff guidance or idempotency elsewhere, including number purchases and click-to-call (6 of 15). The site claims 99.999 per cent voice uptime, but no SLA was found in the Terms (0). The API and click-to-call carry no beta label, while the new buy experience is rolling out gradually (10). 0+5+5+6+0+10 = 26.

Telnyx Voice API + MCP 75

Status page at status.telnyx.com (run on incident.io) with a readable incident feed and history (20). Two incidents Telnyx itself marked major hit voice or the API in the 90 days to 1 November. One-way or degraded audio on inbound and outbound calls from 16:00 UTC on 10 September, marked resolved at 01:43 on 11 September, and intermittent 5XX responses across API endpoints and portal 2FA login for about 2 hours on 23 September. Minor ones included one-way or dead air audio, call drops and missing recordings on 7 August (partial outage, mitigated after 34 minutes), delayed call recordings and conferences on 9 and 10 September, 1 hour 18 minutes of API v2 processing delays on 13 October, and on 28 October about an hour of 503s on credential creation only (POST /v2/telephony_credentials). On 21 October, between about 18:17 and 19:20 UTC, a network fault caused intermittent failures across services, with some outbound call setups failing and Call Control dials intermittently returning 500. Telnyx posted it two days later with no impact level, and the portal's outages totalled about 20 minutes. Intermittent errors on some calls read as partial, so it isn't counted as a third major. Two majors fall between the checklist's one major and several, so we gave half the one-major mark (5). Outbound dials are capped at 30 a second, counted over fixed 5-second windows of 150 per region, re-read on 1 November (15). The rate-limiting page documents 429 with error code 10011, Retry-After and x-ratelimit headers, bounded exponential backoff with jitter, and retrying only safely repeatable operations, per the 17 October check, not re-read on 1 November (15). A machine-readable SLA at telnyx.com/ai/sla.json states 99.99 per cent for core voice and messaging, with credits of 10, 25 and 50 per cent below 99.99, 99.9 and 99.0. pricing.md lists a custom SLA on committed plans and credits on Enterprise, so who qualifies is unclear (10). Voice API is generally available (10). 20 + 5 + 15 + 15 + 10 + 10 = 75.

Maintenance & community Telnyx Voice API + MCP +45

didlogic Voice API 38

Release notes dated by month, the newest September 2026 (click-to-call API and WebSocket calls), about 37 to 67 days before this check (20). Entries in August and September and the July self-service API within the 90 days, dated by month only, so fewer than three dated changes can be confirmed (10). Release notes, phone and email support, and a partner programme, with no evidence read of reply times (8 of 15). No official server-side SDK, and the MCP server isn't in the official registry (0). No package to assess (0). 20+10+8+0+0 = 38.

Telnyx Voice API + MCP 83

telnyx-node v7.29.0 tagged on 2026-10-28, after v7.27.0 and v7.28.0 on 21 and 22 October (30). 17 telnyx-node releases in the 90 days to 1 November, from v7.13.0 on 4 August to v7.29.0 (20). Closed service with public release notes, the newest dated 30 October 2026 (voice entries on 20 October for AssemblyAI keyterms on Voice AI Assistants and 28 October for Pipecat agents on Telnyx Edge), and a support channel. We couldn't read GitHub issue replies (8 of 15). Current official SDKs, and the MCP is in the official registry as io.github.team-telnyx/telnyx, though the newest registry version is still 6.29.3 of March 2026 (15). Release automation runs in CI (10). 30 + 20 + 8 + 15 + 10 = 83.

Agent ergonomics Telnyx Voice API + MCP +33

didlogic Voice API 57

Call records take filters and CSV export, and numbers search by country, region and city (18 of 25). Filtering on calls and numbers, with paging not confirmed on every list (14 of 20). One error envelope with field messages and 404 for unknown ids (14 of 20). No idempotency key on purchases or click-to-call. MCP annotations weren't readable without a sign-in (3 of 20). Few required fields, no official SDK beyond the browser Voice SDK (8 of 15). 18+14+14+3+8 = 57.

Telnyx Voice API + MCP 90

List endpoints take page size and number, with no field selection (15 of 25). Filters and pagination on list endpoints (20). JSON errors with a code, title and detail, and a documented code list (20). Call commands take a command_id, and Telnyx ignores a repeat with the same command_id on the same call, so a retried command is safe (20). Official SDKs in Node, Python and more, and a call needs connection_id, to and from (15).

Payments & pricing Telnyx Voice API + MCP +27

didlogic Voice API 38

No x402, MPP or L402 (0). Per-minute call rates and monthly number prices are public by country, marked as indicative (18 of 20). Free test credit with no card, and a 30-day trial number for verified company emails (20). Signup and key creation happen in the portal (0). 0+18+20+0 = 38.

Telnyx Voice API + MCP 65

x402 exists on Telnyx's own API at /v2/x402/credit_account (USDC on Base), with MPP at /v2/machine-payments/account-credit, but both top up account credit rather than pay per call. The x402 skill says x402 is behind a per-account feature flag and returns 403 where it isn't enabled, while the MPP skill names no such flag. Per-payment limits are stated only in 422 errors (25 of 40). Per-minute voice, SIP, number and add-on rates published without a login, also as pricing.md (20). No free credit, a new account starts at zero (0). An agent can sign up through /v2/bot_challenge and /v2/bot_signup, collect the email link, mint a key at /v2/api_keys and fund the account by MPP with Tempo USDC, or x402 where enabled, with no browser (20).

Transparency & trust Telnyx Voice API + MCP +14

didlogic Voice API 58

Closed service with long, clear terms naming DID Logic PTE. LTD. in Singapore (15 of 30). The privacy policy commits to data minimisation and says call content isn't monitored except for requested recording, but gives no retention periods (12 of 30). No deprecation policy, though the docs explain backward-compatible identifier changes (5 of 20). Twelve points of presence are claimed, with no sub-processor list or data locations found (5 of 20). 15+12+5+5 = 37.

Telnyx Voice API + MCP 72

Closed service with clear terms (15). Privacy policy covering retention, a Telnyx DPA referenced from the sub-processor page, and a list of sub-processors re-read on 17 October. We didn't find stated retention periods for call records and recordings (25 of 30). No deprecation policy or dated deprecation notices found for voice (0 of 20). Each sub-processor is listed with its entity, address, products and data categories, AI sub-processors are separated and apply only when enabled, and the page has change alerts (15 of 20).

Schema & documentation Telnyx Voice API + MCP +6

didlogic Voice API 87

Public OpenAPI 3.0.3 file with 53 operations (25). llms.txt and Markdown pages (10). Every operation is described, and the descriptions explain cross-version identifiers and when to poll, such as click-to-call progress (16 of 20). Typed request bodies with required fields and enums in the spec (12 of 15). Examples, a standard error envelope ({"errors":{"base":[...]}}) and 401, 403, 404 and 422 responses on most operations (12 of 15). Paths versioned v1 and v2, and release notes dated by month (12 of 15). 25+10+16+12+12+12 = 87.

Telnyx Voice API + MCP 93

Public OpenAPI 3 spec in the team-telnyx/openapi repository, synced from Telnyx's internal repository on 16 October 2026 (25). llms.txt on both developers.telnyx.com and telnyx.com, with Markdown doc pages and machine-readable pricing (10). One reference page per call command with purpose and parameters, but little guidance on when not to use a command (15 of 20). Typed JSON bodies with enums, for example the stream track and bidirectional mode (13 of 15). Request examples per command and a page of API error codes (15). Versioned /v2 path and public release notes (15).

Score by category

CategoryWeight this rundidlogic Voice APITelnyx Voice API + MCPEdge
Reliability16%202675Telnyx Voice API + MCP +49
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.28793Telnyx Voice API + MCP +6
Agent ergonomics13%16.25790Telnyx Voice API + MCP +33
Security & auth14%17.54645didlogic Voice API +1
Payments & pricing10%12.53865Telnyx Voice API + MCP +27
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.83883Telnyx Voice API + MCP +45
Transparency & trust7%8.85872Telnyx Voice API + MCP +14
Negative events≤1500
TotalD 49.8/100BB 74.3/100

Facts side by side

Factdidlogic Voice APITelnyx Voice API + MCP
KindHTTP APIHTTP API
VendorDID Logic PTE. LTD.Telnyx
Hosted endpointhttps://mcp.didlogic.com/mcphttps://api.telnyx.com/v2
TransportsHTTP, websocket, Streamable HTTPHTTP, Streamable HTTP, stdio
AuthOAuth or keyOAuth or key
PricingPay per usePay per use
Price for phone numbers$2 per month (plan)$1 per month (plan)
x402nopayer tooling only
LicenceProprietary service under the didlogic Terms of ServiceMIT
Tools exposednone6
Read-only variant documentednoyes
llms.txtyesyes
MCP registrynot listedio.github.team-telnyx/telnyx
Last release2026-09-302026-10-28
Terms last updatedno date givenno date given
Privacy policy last updatedno date given2026-03-01
Customer content may train modelsnot found in the textnot found in the text
Terms restrict automated accessnot found in the textnot found in the text
Terms restrict benchmarkingnot found in the textnot found in the text
Terms or service can change without noticenot found in the textnot found in the text
Arbitration or class-action waiveryesyes
Popularitynone197 stars, 417k npm/wk, 179k PyPI/wk
Agent reviewsnone3.5/5 (8)

How the scores have moved

Verdicts

didlogic Voice API

didlogic pairs a public OpenAPI file with 53 described operations, published per-minute and number prices and free test credit with WebSocket calls for voice AI and a remote MCP server. There's no status page or SLA, keys carry full account access, and purchases and calls have no idempotency key.

Telnyx Voice API + MCP

About $0.007 a minute all-in for US outbound ($0.002 Voice API plus $0.005 termination). x402 and MPP only top up credit, they don't pay per call.

Before you call either

didlogic Voice API

  1. Create the key under API & Webhooks in the portal; ignore the older get-started line about asking an account manager
  2. Confirm with the user before POST /api/v2/numbers/purchase or click-to-call; both spend the prepaid balance with no idempotency key
  3. For WebSocket calls, set a_type: stream and implement didlogic's message protocol on your endpoint
  4. Back off on 429 from recording endpoints using Retry-After
  5. Expect the MCP server only on the Plus plan

Telnyx Voice API + MCP

  1. Create a Call Control application first. POST /v2/calls needs its connection_id
  2. Fund a new account through MPP or /v2/x402/credit_account before buying a number; a 403 from x402 means the flag isn't enabled for the account
  3. Only one media stream or fork runs per call, and starting a fork replaces the websocket stream
  4. Add the Voice API fee and SIP trunking rate together when pricing a call, and $0.10 per transfer
  5. Set a unique command_id on every call command, so a retry after a timeout is ignored rather than repeated

Questions

Which is better for AI agents, didlogic Voice API or Telnyx Voice API + MCP?

Telnyx Voice API + MCP scores 74.3 (BB) on agent readiness against didlogic Voice API's 49.8 (D), and leads in 6 of 7 scored categories.

Which is cheaper for phone numbers, didlogic Voice API or Telnyx Voice API + MCP?

Telnyx Voice API + MCP, at $1 per month (plan) against $2 per month (plan) for didlogic Voice API. These are the vendors' published prices for the job.

Do didlogic Voice API and Telnyx Voice API + MCP need an API key?

Both take an API key or an OAuth sign-in.

Can an agent call didlogic Voice API and Telnyx Voice API + MCP without installing anything?

Yes. didlogic Voice API has a hosted endpoint at https://mcp.didlogic.com/mcp and Telnyx Voice API + MCP at https://api.telnyx.com/v2.

Other comparisons with didlogic Voice API or Telnyx Voice API + MCP

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